I always thought that the Mercenary adds his strength in battle only everytime when you paid to him.

I need original text of the "Mercenary" card. Could anybody help me?

If you want the Mercenary as your Follower, pay 1 gold. If not, he waits here for a character willing to pay him. While he is your Follower he will add 3 to your Strength in battle until the end of the turn provided you pay 1 gold. You may only pay 1 gold once per turn.

Thanks a lot. My version has lack of some instruction.