Ch'rell, Enraged Prisoner

When Ch'rell, Enraged Prisoner enters the battlefield put a rage counter on it.
Whenever a Foot Clan creature enters the battlefield under your control, put a rage
counter on Ch'rell Enraged Prisoner.
When there are three rage counters on Ch'rell,
Enraged Prisoner, exile it and search your library
for a Shredder Planeswalker card and place
it onto the battlefield.