Same, 1.6k here ... Knowing that now, it opens quite a lot of doors in regard to PU strategies, always wanted to have a way to prevent the AI from Rivaling you and going hostile - Well, hostile still isn't solved though if they suddenly desire like half your land
Austria rivaled me with 100 trust, they still can hate you if you have a lot of AE with them unfortunately. But if they are a bit further, it's gr8 to secure. I'm just getting the GB PU in my recent run, and a Spanish and a Portugal PUs are on the way too!
Very helpful guide! I have over 4000 hours on eu4 and I've always found PU's a bit dodgy and RNG-like but this is actually an amazing strategy to kind of ensure to get these massive unions, dodging AE and such. Goes to show you never really stop learning new stuff (on eu4).
Feeding future PU targets is something I love doing with Burgandy if I can get inheritance, or Milan as emperor/france! it's basically a cheat code lol! on hard difficulty you can't actually place an heir with favours, but it's still useful for trust.
When you break the alliance, Are they still not going to rival you? I know that you can keep their relations pretty high even without an alliance, but I believe that the trust decays pretty quickly once you are no longer allied to someone. I appreciate all your EU4 Guides!
Trust does decay, but usually only like 1 per year. The best way to mitigate this is stock pile a lot of favors to keep boosting trust even after the alliance is broken. As long as they have 80 trust, they can not rival you.
From what I understand he just wanted to play a bit and said he was going to play a full game if he got the burgundian PU, and here we are. He made a separate channel called "basedmonk" where the latest upload is 5 days old.
One extra thing to note with this strategy is that since they are not a subject they can complete more missions and tag switch as well. Meaning Spain might PU naples and austria if strong enough.
Thanks for this guide, it's going to be very helpful. I have a game very similar to this one, where my goal was just to play as Holland, consolidate the lowlands, and form the Netherlands, since I've never done it before. I got France and Austria to support my independence, and also gave independence to the other lowlands PUs in the peace deal so I could take them over without having to fight against Burgundy again as well. Things were going decently well, I had begun conquering the Belgian region and some of the northern lowlands, when, out of nowhere, I was elected emperor. Ended up getting the BI as a result (still don't really know why they picked me, since I'd made no attempt at diplomacy there and even had claims on all of their provinces I bordered,) and it's just snowballed from there. I'm now planning on PU'ing my longtime ally France, and using them as a hammer to smash England. While I'm familiar with using favors to place a relative on an ally's throne (a tactic I'm using to great effect in my Austria game, where there's now a Habsburg ruling Muscovy,) this guide filled in some details here and there I was lacking regarding the best way to go about doing it. Looking forward to utilizing these tactics in my quest to become disgustingly wealthy through trade.
This is great and all but the biggest problem is then you have to win a war against them to get the PU, which would be insanely difficult if they are so fed from you giving them provinces for trust. You would need a big coalition, would need a lot of setup.
I take it you switch your own dynasty mostly as a way to speed up the PU process? I have done the same and gotten I believe 3 GPs as PUs solely via installing heirs, but it certainly is a slower process (and requires much more focus. Very easy to miss a monarch or heir death in another country.)
You can set monarch deaths as a notification in the bottom right notification box! I have it set to do a pop up every time an interesting nations monarch dies!
Can we get spreadsheet in excell where u explain point by point and maybe add tips as well? It could be handful while playing. It could be simplified version and more advanced as well in second spreadsheet.
Planning on trying this in a game of Anbennar. For anyone familiar, I want to get a Verne PU as Neckcliffe instead of conquering the high AE Empire land
What is the novelty in this? not sure I fully understood the nuance. Isn't this the same case as having a large ally and using the request heir for favors and puing later on?
Haven’t watched the video yet: isn’t it incredibly easy to pu countries just by saving up 90 favors, installing heir on throne claiming throne, breaking alliance, waiting the truce then declaring? Or even if you get lucky just gaining it naturally.
I actually have 2k house on this game. propbably 5 of those are sp and the rest is multiplayer gameplay.. and I find this interesting.. make me wanna play more SP and try stuff out.
can you do a guide on the "free pu" ie their ruler dies without an heir and they fall under your personal union. I've had instances where for example I share dynasties with muscovy, his ruler dies with no heir, cause I savescum, then a new ruler just appears.
there are nothing hard about this. there are 3 phases. im not sure about exact amount of years for which they last but i give you idea. first on is when "Noble of will succeed to the throne" at this stage you will not be able get free PU. Which noble succeed calculated on royal marriages overall prestige and development. next one "will fall into pu" this works the same except the fact that you will actually get pu. and last one "will lead to succession war with" same as previous one but major power will be able to press their claims. during the game this phases will repeat. and this phases are answer why sometimes rivaled countries are in pu or you randomly get an heir of different dynasty when ruler die. worth to mention that war will automatically reset this counter to phase one for whole war period. which were mentioned in this guide. it applies to every christian country in the world..
you have "detach siege" button on your army. shortcut is "d" it detaches exact number of units required to siege the province the army is in. so you can detach siege and continue moving with your deathstack. or spam "d" and you get bunch of 1 regiments to spread out and carpet siege. it also works on forts, if you detach siege on fort, it will detach exact number of units required to successfully siege the fort. you must use that if you dont want to suffer too much attrition when sieging.
I just got a PU on Poland Lithuania yesterday in late game as GB at something around 1770 with no war around it just a notification that PU formed. That Poland was massive 3200 Development and owned Muscovy, Berlin, and all the was down to Constantinople with an 980k Force limit being absolutely loyal to me who only had 330k. I still had another PU over France and Denmark as an 750 development Vassal that was somehow still at 0% for independence but had an 260k Army and 230ship navy. So I could pretty much just declare war on any nation without needing to do anything. Felt so great. But all my Ideas groups were just economy and giving subject less will for independence. So my own army was entirely trash.
I’m new to the game and You said your not demonstrating any skill but whatever that was at 1:40 must take some skill right? Lovely content as always, I’m honestly not used to hearing the kiwi accent on gaming channels so it’s refreshing.
Haven't watched the video yet: I once PUed great Britain through claim throne without having the same dynasty. I was in a queen consort regency. The queen was the same dynasty as Britain.
@@ramp597 if you have a consort Regency you can still declare war. There are types of Regency Consort regency means your old rulers consort is the regent. The other type of regency means it is just some random dude, with that type of regency you cannot declare war
You don't have to break the alliance if you just want to keep them as an attack dog until they have a ruler that dies. I got a PUT over Castile, whom I helped to become Spain and there was to be a succession war with PLC but I was allied with them in a war, so they didn't contest. Boom, PU over Castile, and Muscovy by 1570, that's also with the Burgundian inheritance, which strangely hasn't fired the final event where I inherit them outright, and it's been over 30 years haha. Now I am supporting my ruler on the throne of the Commonwealth, if it hasn't changed, in the early 1600s he can flip monarch with your aged king and no heir on the throne.
Could you do a video for tips and tricks for a mid-late game byz campaign ik you have to buy those TC they are op for increasing your force limit for both navy and army but is there any other ones
This 80 trust not always true. You should not expand into ally area of interest. For example, Spain will get permaclaims in Netherlands, and you will lose him as friendly.
There appears to be a chance that the nation that you want to PU gains a restore union casus belli on you once you become their dynasty, i'm not sure what caused it to happen to me though
i think you are reffering to "claim throne" option in diplomacy. if you same dynasty as another country and if they dont have heir you can "claim throne" and declare war for PU
restore union casus belli you get when you lose pu with someone, or with mission trees and events. like france always get restore pu over naples and milan. in evnets and missions
one problem with this strategy is inability to manage your AE properly. technically you can feed up the whole region to your pu target. but the way AE works in this game it will dramatically affect all countries in the world. I can see only one way how to use it without collateral damage. prepare country like castile in Europe and go away from Europe with your conquests. this way you will be able to enforce your PU without creating uncontrolled coalition for the whole HRE. and worth to mention that this is only useful for Christians which means you either want to save up some country for later or come to Europe and convert to Christianity when there will be no minor countries around. but second option will create huge amount of problems if you are not a horde which leads us to a conclusion. that this strategy is worth to use but in very special cases. as well i would like to add one more shenanigan to this strategy. we know that pu's are less likely to revolt against you. AE calculated based mainly on amount of development of province. and there are a strategy of creating "return core" CB. basically it works same as ally feeding but in reverse. when we established desired dynasty on both thrones we can simply dismantle that country by feeding another countries. which we can use to our advantage. when we get to the minimal amount of AE for PU we can enforce it and start to return it's cores. cores lasts for 50+ years which gives us ability to reconquer all provinces for 50-75 % AE less combined. i believe that it may be the best strategy for conquering HRE fast and for low AE. and wanna say couple words for this creator. appreciate your effort to populate this game your content is pretty impressive and helps newcomers to understand advanced shenanigans of this game.
You don't need to wait 5 years for the vassal thing, just declare if they're small and raise your stability. You can easily get a PU on Ming if you vassalise them, make them Catholic, put your dynasty on their throne, and then do a little shaky shaky truce breaky to get them under a PU. You can then feed them all of their cores and all of East Asia really and they'll never be disloyal.
So you can declare war on them. Once the truce expires, the other target has a guaranteed low legitimacy heir (because you made them adopt your dynasty). The low legitimacy heir means you can claim throne. If you have them the heir and didn’t change your dynasty, you have to wait an unknown amount of time until the target country has no heir. Because you don’t know if, when an heir becomes leader, they will automatically get an heir as well.
@@melon_man_dan6888 I didnt fully understand. So you royal marry them, he gets the castille ruler as his dinasty. He puts the trust to over 80, he breaks alliance and royal marriages him. And then?
i knew most of this except the 80 trust preventing rival well i most of my games i try put my dynasty on most thrones in europe when i play in case of gaining the pu best luck i have had must have been as france, when i pud, aragon in 30 years and austria at like 1560 i always think of "let me lay the ground work for pu's" but i never bother to actually pu anyone because, i want challenge, i want to enjoy not to minmax shit out of my game
80 trust is useless in colonial walkthrough till PDX fix AI point of interest. Got ottoman 100 trust break instantly because they see my colonial mexico, beware if u play colonial walkthrough
Im sorry but this is just nonsense.. Feeding nation like Castile more land is just useless. Trastamara is a really strong dynasty and they DO NOT lack heirs about 98% of the time. What u r talking about here is pure RNG. Nothing to do with brains or skills or "shady stuff"..
Just have a royal marriage with castille and other countries with Trastamara and let your King die. You will always get a Trastamara. From there on its just a matter of time for the other countries with the same dynasty to not have a heir. You can claim, break alliance and trucebreak to get the PU for sure (as long as you win the war).
My key learning in this video after 2.5k hrs:
Having 80+ trust prevents your ally from rivaling you 😅
Same here with 2.3k 🤣
Same, 1.6k here ... Knowing that now, it opens quite a lot of doors in regard to PU strategies, always wanted to have a way to prevent the AI from Rivaling you and going hostile - Well, hostile still isn't solved though if they suddenly desire like half your land
Austria rivaled me with 100 trust, they still can hate you if you have a lot of AE with them unfortunately. But if they are a bit further, it's gr8 to secure. I'm just getting the GB PU in my recent run, and a Spanish and a Portugal PUs are on the way too!
2.8k and yes
I really enjoy learning from your experience in Eu4, please do more informative guides/videos.
Very helpful guide! I have over 4000 hours on eu4 and I've always found PU's a bit dodgy and RNG-like but this is actually an amazing strategy to kind of ensure to get these massive unions, dodging AE and such. Goes to show you never really stop learning new stuff (on eu4).
Been waiting for this guide ever since you mentioned you were gonna upload something like this in the first PU guide. Thanks for the upload!
Feeding future PU targets is something I love doing with Burgandy if I can get inheritance, or Milan as emperor/france! it's basically a cheat code lol!
on hard difficulty you can't actually place an heir with favours, but it's still useful for trust.
I need your help for the next byz guide : if you read all the ottomans buff we are fucked as players.
Ik I was rick crying in TWD when they announced that
the ottomans will only be OP in the hands of a player tbh
Strategy remains pretty much exactly the same, take gelibolu quickly while the ottos are busy in the east and they just cant cross
I've already learned this strat just by watching your old streams. Thank you PU king :)
Great to see new vids coming out!
Thanks for all your teachings !
When you break the alliance, Are they still not going to rival you? I know that you can keep their relations pretty high even without an alliance, but I believe that the trust decays pretty quickly once you are no longer allied to someone.
I appreciate all your EU4 Guides!
Trust does not decay as far as i know unless you got in a war agaisnt other nation or something
Trust does decay, but usually only like 1 per year. The best way to mitigate this is stock pile a lot of favors to keep boosting trust even after the alliance is broken. As long as they have 80 trust, they can not rival you.
Wouldn't really matter. Once they're your PU they lose the relations malus since they can no longer be your rival as your subject.
@@2upie2u If they rival you before they are heirless, you can't royal marry them to claim throne.
I may carry favors with them without an aliance and exchange them for trust later on.
Just did this in my Germany game! Good to know I’m keeping up with you 😊
The other day I was thinking about this strat I should have tried before. I thought "this is really a budget monk move" and now you upload this video
I thought he was going to stop eu4 on this channel? Wait his video is gone too?
Changed his mind.
@@_DaWe_ was there a vid on it?
From what I understand he just wanted to play a bit and said he was going to play a full game if he got the burgundian PU, and here we are. He made a separate channel called "basedmonk" where the latest upload is 5 days old.
One extra thing to note with this strategy is that since they are not a subject they can complete more missions and tag switch as well. Meaning Spain might PU naples and austria if strong enough.
Thank you for another great video! :)
Thanks for this guide, it's going to be very helpful. I have a game very similar to this one, where my goal was just to play as Holland, consolidate the lowlands, and form the Netherlands, since I've never done it before. I got France and Austria to support my independence, and also gave independence to the other lowlands PUs in the peace deal so I could take them over without having to fight against Burgundy again as well. Things were going decently well, I had begun conquering the Belgian region and some of the northern lowlands, when, out of nowhere, I was elected emperor. Ended up getting the BI as a result (still don't really know why they picked me, since I'd made no attempt at diplomacy there and even had claims on all of their provinces I bordered,) and it's just snowballed from there. I'm now planning on PU'ing my longtime ally France, and using them as a hammer to smash England. While I'm familiar with using favors to place a relative on an ally's throne (a tactic I'm using to great effect in my Austria game, where there's now a Habsburg ruling Muscovy,) this guide filled in some details here and there I was lacking regarding the best way to go about doing it. Looking forward to utilizing these tactics in my quest to become disgustingly wealthy through trade.
Im sure you know this by now but BI goes to emperor, because austria is always the the emperor it goes to them
Havnt played eu4 in awhile. But being able to use favors now to spread your dynasty is now huge and makes PUs way less RNG dependent which is nice
This is great and all but the biggest problem is then you have to win a war against them to get the PU, which would be insanely difficult if they are so fed from you giving them provinces for trust. You would need a big coalition, would need a lot of setup.
Im pretty sure he's talkingg about the "Personal Union on Monarch Death" thing instead of claiming the throne, hence needing more prestige
Damn! If there is a EU4 PRO that guy is you, Monk. Absolutely beatiful
I take it you switch your own dynasty mostly as a way to speed up the PU process? I have done the same and gotten I believe 3 GPs as PUs solely via installing heirs, but it certainly is a slower process (and requires much more focus. Very easy to miss a monarch or heir death in another country.)
You can set monarch deaths as a notification in the bottom right notification box! I have it set to do a pop up every time an interesting nations monarch dies!
Can we get spreadsheet in excell where u explain point by point and maybe add tips as well? It could be handful while playing. It could be simplified version and more advanced as well in second spreadsheet.
Planning on trying this in a game of Anbennar. For anyone familiar, I want to get a Verne PU as Neckcliffe instead of conquering the high AE Empire land
This is brilliant
Dude this is crazy!!!
Lore of Eu4: How to PU like a Gigachad momentum 100
Thank you!
4k hours and I didn't notice the "request relative as heir" button :)
The request relative as heir option should only be available on Very Easy and Normal tbh
glad you decided not to stop : D
Question. What tag will you get after all the steps?
What is the novelty in this? not sure I fully understood the nuance. Isn't this the same case as having a large ally and using the request heir for favors and puing later on?
This dude one here calling Bayreuth Beirut
Omg his eu4 is back :D
Haven’t watched the video yet: isn’t it incredibly easy to pu countries just by saving up 90 favors, installing heir on throne claiming throne, breaking alliance, waiting the truce then declaring? Or even if you get lucky just gaining it naturally.
PU King :)
I actually have 2k house on this game. propbably 5 of those are sp and the rest is multiplayer gameplay.. and I find this interesting.. make me wanna play more SP and try stuff out.
More than 1500 hours and I still didn't know about the 90 trush avoiding to be rivaled xD
Budgetmonk not making a video about PUs every 30 days challenge (IMPOSSIBLE)
love ya ;)
Title alone deserves a thumb!
his way of carpet siegeing left me numb...
Ah rip, I didn't know you could force a relative to be their heir, but I always play very hard anyway though
can you do a guide on the "free pu" ie their ruler dies without an heir and they fall under your personal union. I've had instances where for example I share dynasties with muscovy, his ruler dies with no heir, cause I savescum, then a new ruler just appears.
there are nothing hard about this. there are 3 phases. im not sure about exact amount of years for which they last but i give you idea. first on is when "Noble of will succeed to the throne" at this stage you will not be able get free PU. Which noble succeed calculated on royal marriages overall prestige and development. next one "will fall into pu" this works the same except the fact that you will actually get pu. and last one "will lead to succession war with" same as previous one but major power will be able to press their claims. during the game this phases will repeat. and this phases are answer why sometimes rivaled countries are in pu or you randomly get an heir of different dynasty when ruler die. worth to mention that war will automatically reset this counter to phase one for whole war period. which were mentioned in this guide. it applies to every christian country in the world..
Very noice ck strategy
Yeah, I feel like Russia and Britain you can 100% PU in the game and sometimes other ones too
Sorry for the irrelevant question, but how do you send out individual units from group like that from 1:45?
you have "detach siege" button on your army.
shortcut is "d"
it detaches exact number of units required to siege the province the army is in.
so you can detach siege and continue moving with your deathstack.
or spam "d" and you get bunch of 1 regiments to spread out and carpet siege.
it also works on forts, if you detach siege on fort, it will detach exact number of units required to successfully siege the fort.
you must use that if you dont want to suffer too much attrition when sieging.
I just got a PU on Poland Lithuania yesterday in late game as GB at something around 1770 with no war around it just a notification that PU formed.
That Poland was massive 3200 Development and owned Muscovy, Berlin, and all the was down to Constantinople with an 980k Force limit being absolutely loyal to me who only had 330k.
I still had another PU over France and Denmark as an 750 development Vassal that was somehow still at 0% for independence but had an 260k Army and 230ship navy.
So I could pretty much just declare war on any nation without needing to do anything. Felt so great. But all my Ideas groups were just economy and giving subject less will for independence. So my own army was entirely trash.
I hope you conquered the world.
I’m new to the game and You said your not demonstrating any skill but whatever that was at 1:40 must take some skill right? Lovely content as always, I’m honestly not used to hearing the kiwi accent on gaming channels so it’s refreshing.
Haven't watched the video yet: I once PUed great Britain through claim throne without having the same dynasty. I was in a queen consort regency. The queen was the same dynasty as Britain.
How did you declare war while having a regency
@@ramp597 if you have a consort Regency you can still declare war. There are types of Regency
Consort regency means your old rulers consort is the regent.
The other type of regency means it is just some random dude, with that type of regency you cannot declare war
@@bandtown8587 I didn't know that, thanks
I did not know that favour thing with them rivaling you I gotta write this down
liking the cap
You don't have to break the alliance if you just want to keep them as an attack dog until they have a ruler that dies. I got a PUT over Castile, whom I helped to become Spain and there was to be a succession war with PLC but I was allied with them in a war, so they didn't contest. Boom, PU over Castile, and Muscovy by 1570, that's also with the Burgundian inheritance, which strangely hasn't fired the final event where I inherit them outright, and it's been over 30 years haha. Now I am supporting my ruler on the throne of the Commonwealth, if it hasn't changed, in the early 1600s he can flip monarch with your aged king and no heir on the throne.
dang
I tried It with France as Castle 3 games and did not work
It always, always had a heir
Could you do a video for tips and tricks for a mid-late game byz campaign ik you have to buy those TC they are op for increasing your force limit for both navy and army but is there any other ones
Is it still true that if you have a PU you can't be PU'ed. So if you have any PU already, do you really need to be at war to avoid succession crisis?
Yes. You won't have succession crisis if you have a PU so no need for constant war.
Kind of important to mention then @BudgetMonk
This 80 trust not always true. You should not expand into ally area of interest. For example, Spain will get permaclaims in Netherlands, and you will lose him as friendly.
100 prestige and 10 Diplo rep, watch the PUs just roll in.
i thought u announced to stop making eu4 content, im glad you ddint
even with 80 trust they can still turn hostile if they border you and want your provinces, right?
if you wait like 30 years yes they will rival you but the idea is to pu them when their ruler dies, so it won't take 30 years if you plan it well
You can take provinces they don't want although the AI is dumb and will sometimes set your capital area as provinces of high interest for no reasonn
There appears to be a chance that the nation that you want to PU gains a restore union casus belli on you once you become their dynasty, i'm not sure what caused it to happen to me though
i think you are reffering to "claim throne" option in diplomacy.
if you same dynasty as another country and if they dont have heir you can "claim throne" and declare war for PU
restore union casus belli you get when you lose pu with someone, or with mission trees and events.
like france always get restore pu over naples and milan. in evnets and missions
Thats why , after 1800 h , I am still a noob in this game lol
What do you mean by limitation of years you can play the game?
game ends in 1821
My question is how do you carpet siege like that :|
Got to my channel search bar and type carpet siege.
one problem with this strategy is inability to manage your AE properly. technically you can feed up the whole region to your pu target. but the way AE works in this game it will dramatically affect all countries in the world. I can see only one way how to use it without collateral damage. prepare country like castile in Europe and go away from Europe with your conquests. this way you will be able to enforce your PU without creating uncontrolled coalition for the whole HRE. and worth to mention that this is only useful for Christians which means you either want to save up some country for later or come to Europe and convert to Christianity when there will be no minor countries around. but second option will create huge amount of problems if you are not a horde which leads us to a conclusion. that this strategy is worth to use but in very special cases. as well i would like to add one more shenanigan to this strategy. we know that pu's are less likely to revolt against you. AE calculated based mainly on amount of development of province. and there are a strategy of creating "return core" CB. basically it works same as ally feeding but in reverse. when we established desired dynasty on both thrones we can simply dismantle that country by feeding another countries. which we can use to our advantage. when we get to the minimal amount of AE for PU we can enforce it and start to return it's cores. cores lasts for 50+ years which gives us ability to reconquer all provinces for 50-75 % AE less combined. i believe that it may be the best strategy for conquering HRE fast and for low AE. and wanna say couple words for this creator. appreciate your effort to populate this game your content is pretty impressive and helps newcomers to understand advanced shenanigans of this game.
You don't need to wait 5 years for the vassal thing, just declare if they're small and raise your stability. You can easily get a PU on Ming if you vassalise them, make them Catholic, put your dynasty on their throne, and then do a little shaky shaky truce breaky to get them under a PU. You can then feed them all of their cores and all of East Asia really and they'll never be disloyal.
Mind boggling depth. Will re-watch. Why have to be not-allied to get the PU?
So you can declare war on them. Once the truce expires, the other target has a guaranteed low legitimacy heir (because you made them adopt your dynasty). The low legitimacy heir means you can claim throne.
If you have them the heir and didn’t change your dynasty, you have to wait an unknown amount of time until the target country has no heir. Because you don’t know if, when an heir becomes leader, they will automatically get an heir as well.
@@melon_man_dan6888 Oh, yeah. Thanks!
@@melon_man_dan6888 I didnt fully understand. So you royal marry them, he gets the castille ruler as his dinasty. He puts the trust to over 80, he breaks alliance and royal marriages him. And then?
i knew most of this except the 80 trust preventing rival
well i most of my games i try put my dynasty on most thrones in europe when i play in case of gaining the pu
best luck i have had must have been as france, when i pud, aragon in 30 years and austria at like 1560
i always think of "let me lay the ground work for pu's" but i never bother to actually pu anyone because, i want challenge, i want to enjoy not to minmax shit out of my game
favors are so broken
First
80 trust is useless in colonial walkthrough till PDX fix AI point of interest. Got ottoman 100 trust break instantly because they see my colonial mexico, beware if u play colonial walkthrough
Having THE MESSAGE subliminal is the better strategy anyways.
Im sorry but this is just nonsense.. Feeding nation like Castile more land is just useless. Trastamara is a really strong dynasty and they DO NOT lack heirs about 98% of the time. What u r talking about here is pure RNG. Nothing to do with brains or skills or "shady stuff"..
Just have a royal marriage with castille and other countries with Trastamara and let your King die. You will always get a Trastamara. From there on its just a matter of time for the other countries with the same dynasty to not have a heir. You can claim, break alliance and trucebreak to get the PU for sure (as long as you win the war).
They lack and heir about 50% of the time on every single ruler or heir death.