This game forces you to change your strategy!

[Kolorabi]

Make some more tempting targets. For instance, get a unit with high initiative (like griffins, sprites or dryads) and send them to cause havoc. Dryads can make thorns, which the enemy AI is often very keen on killing first. You can also use the spell which makes a clone of one of your armies to create what's basically a kamikaze troop, that hurries into the enemy's rank to prevent them from attacking you.

Also, there's a might-skill that gives you higher initiative during the first round. It's quite useful, as it allows you to get the first hits (and often your elf archers will get their turn before any of the opponents has a chance to do anything).