Gathering Tavern

Gathering Tavern isn't a creature unless a creature deals damage to a player this turn.
{t}: Put a Hit counter on target creature. Activate
only if Gathering Tavern is a creature.
{b}{r}: Double the number of Hit counter on target
permanent. Activate only if Gathering Tavern has a
Hit counter.
If Gathering Tavern has 3 or more hit counters, it
is a creature and has +1/+1 for each Hit counter.