The Evolving Chamber

Graft 5 (This artifact enters the battlefield with
five +1/+1 counters on it. Whenever another creature
enters the battlefield, you may move a +1/+1 counter
from this artifact onto it.)
Whenever one or more +1/+1 counters are put
on another creature, you may have The Evolving
Chamber become a copy of that creature until
end of turn, except its a 0/0.
"A fragment of Kraj encased in ingenuity."