i just beat it after going at it again, imma share some tips to help out anyone struggling
1 you wanna go hyper aggressive, especially early on, else santa spams powerful armies at you, always look for an opportunity to take a region, stand down and fortify are useless, you should have like 25-33% of the map captured before you need above 3 guards
2 the instruction and unit caps are very restrictive, elfantry and tanks are the best units to work around them, you'd wanna abandon guards when hitting this cap
3 you wanna focus on making units, resources are not very scarce
for the actual battles
1 try to predict your opponent's moves when you have excess instructions and always do it at the end of the turn so there is the greatest chance of the enemy having already went there
2 make sure to incorporate dodging into your playstyle, dodge their attacks with some of your units
3 know how you should play around weaker and stronger units, and when a unit is really worth keeping for recovery, generally you wanna keep your units early-mid so they recover as units are scarce early on