Taming
Hero ability · Monster ability
For heroes
Taming +X. +X to your roll when you try to tame a monster.
For monsters
Taming X. To buy it you must first roll at least X (plus your Taming bonus); if you fail, it attacks you and stays in the Market.
Heroes with this ability
Merchant 
Druid Cards with this ability 7
Frequently asked questions
If I fail to tame a monster, can I try again in the same turn?
Yes, as many times as you like. Coins are spent only when you succeed, but each failed attempt makes the monster attack you. The exception is monsters that don't attack when you fail (e.g. the Monkey): with those you get one attempt per turn.