I feel the earth Moo under my feet

[Deadpan]

Level 1 characters vs cows? I reckon only two are viable since the key must be to avoid getting hit. Both would use a ranged attack supplemented with charms and Envy jewels:

Barbarian: Howl
Druid: Ravens plus Poison Creeper

You wouldn't need any skillpoints since you could rely on headgear adders.