This is for oddities in the rules that just don't make logical sense.
Deathtouch: So there's basically two types of death touch. One is poison, and one is "turn to stone". For example, a tiny basilisk can turn a bolder to stone and kill it. Or, turn the already stone Garus Rook to stone again.
Archers with anti-air but not long range: So sure, the idea of skeleton archers needing an upgrade is straight out of RTS games. You upgrade your short bows to long bows. But green has a centaur with a gigantic bow that can't shoot more than a short bow.