ANBU

You can have any number of ANBU cards in
your deck.
When ANBU enters the battlefield, flip a coin two times. If you win first time, ANBU's attack is
equal to 3. If you lose first time, it is equal to 2. Simular to thoughtness.
Whenever anbu attacks, flip a coin. If you win,
ANBU gains first strike. If you loose, ANBU deal
combat damage after other creatures.