we'll see
as viking i would love a all in dragon army
just a simple stone skin and some firebreath to rape the enemies
and i think u can correct me if i'm wrong but if your level 4 troops got side effects(burning/poising/icing) you get a HUGE amount of damage
since your level 4 units have a higher total HP than level5's
and you would lose more than the 5's
but all in all it's about how much damage or make the enemy immobile of doing anything on the first 3turns