So I've "discovered" a new strategy. Well, more like I took an existing mechanic and exploited the hell out of it. Essentially, (this is really only good for maps with more than 3 countries and less than... idk 50?), I build up a very large army as quickly as possible. I insult everyone to the point that I could send an ultimatum to them (Opinion <= -10) I then send ultimatums to vassalize (although you could take all provinces for smaller nations) every single other country.

Other things to note: Taxes: A couple ticks above the recommended Good/Investments: Minimum to maintain Research: None Starting Research Points: Max Army Upkeep, then Administration/Tax Income

If anyone has ideas on how to refine this strategy, please comment below

Runs that I used this for: Modern World Victory% (this was the first time I actually used this strat, and I only tried it because my friend thought it would be cool if I could vassalize the 2nd nation.) Sengoku Victory% Ancient Greece Victory%

Note: While this strat is best for Victory%, it could be adapted to Conquer, you would just spam through the turns and annex them once the truce was done. If they declared independence, then you just ignore the declaration, vassalize them again. When it prompts you to acknowledge the declaration the next turn, you just say "Fine", but they're still your vassal. Eventually they give up on independence.