1) If the enemy attacks with Valkyries or other flying units, then you should use the spell of magicians – “Order”. A couple of spells – and nothing will be left of the enemy flying units. I recommend using mages against a large number of flying enemy units.
2) If the enemy sent a lot (15 or more) ground troops to you, then 10-15 steam birds will perfectly destroy them, since they have a large radius of destruction by projectiles.
3) If you are attacked by trolls (up to 6-7), then the pickers can be safely launched forward, since the trolls throw stones from a distance – to throw a stone if the enemy is close and hits him (like warriors, berserkers, pickers, swordsmen, knights and others who strike close), then he has to retreat, and thus we have time to strike them. Rest assured, 5 berserkers are strong enough with upgrades to kill 5 trolls, and 10 pickers are good enough to take down enemy trolls.
4) If you attack or are attacked, then keep in mind that totems are useless against the avengers of fallen units – totems do not damage them.