I've found the Death Splinter, especially team's with Thaddeus Brood, to be a lot of fun to use.
Levelling up the range monsters gives you 3 damage which is alot when some of the enemy only has 2 or 3 health.
Goblin Psychic is always a little pesky due to his tank heal and decent magic and health but thankfully Sha-Vi came in handy.
Cursed Windeku is another death splinter monster that's been serving me well. He reminds me of an SCP monster and that Thorn ability is quite the punisher.