Kylleth, Castle of Traps

Defender
You may play Walls as if they had flash.
Whenever a creature is blocked by a Wall, put a
stun counter on it. A creature with a stun
counter loses all abilities. Walls can attack players
who control permanents with stun counters as
though they did not have defender.
Whenever a Wall attacks and isn't blocked, the defending player loses life equal to the mana
value of permanents they control with stun
counters on them.