Noob question about S:CE

As a rule of thumb:
When choosing to strike in combat, you choose either the

hand strike (always available, only works close range and does strength damage - default strength is 1)

or

You play a strike card to strike.

The fifth edition malkavian deck doesn't actually have any strike cards in it, which can be confusing..
Check the other decks for what strike card (such as roundhouse) looks like. Nosferatu has some.