Design patterns for attacking and defending function of a game

So i'm working on a Turn based attack and defend game and doing some brainstorming on how the actual attacking/defending would work and whether any patterns could apply.

The character and the enemy attack until one is dead.

Could any patterns apply to this? I'm just in the brainstorming phase right now.

The patterns I have to choose from are Strategy, Template, Decorator, Factory, Composite and Observer.

Just looking for some discussion.