Best is titans (if you can wait). And for normal units best is those who use long range to attack (witch, mermaid, succubus, catapult and centour archer ;)
I dont get it why somebody tells that in the end comes 200 units? It makes game much more attractive and you need to use strategy. And best stategy is in this situation save all spell cards and use them all then THEY come ;)
11. on your keyboard write word key. 14. Shake that tree realy hard!. 16. Ball must be dropped from hightest point. 19. Press your mouse right button and then key!. 20. Drop that key from hightest point and he will be with no ball. 21. Use first ball as paddle and second like ball and destroy all paddles in right and left sides. If it helps you know that to do.
To fail a mission you need kill both worm and milos and then go to room that leads to toilet(how to do that and get 4th favor read in help. start game->menu->hint) keep it alive becouse i am bored to write this again and again ;)
 "Epic War 3"){kind=icon}
 "me and the key"){kind=icon}
 "Caravaneer"){kind=icon}
 "Heavy Weapons"){kind=icon}
 "A Small Favor"){kind=icon}