+Pretender (4)
Changeling (This card is every creature type.)
As Bloodline Pretender enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.
When Mairsil, the Pretender enters, you may exile an artifact or creature card from your hand or graveyard and put a cage counter on it.
Mairsil, the Pretender has all activated abilities of all cards you own in exile with cage counters on them. You may activate each of those abilities only once each turn.
You may have Mercurial Pretender enter as a copy of a creature you control, except it has ": Return this creature to its owner's hand."
Enchant creature
Whenever enchanted creature becomes blocked, tap all lands defending player controls.
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