Te Ka, Heartless Fury

Haste, trample, reach, shroud, indestructible
At the beginning of each end step, if you control
an artifact named Heart of Te Fiti, transform
Te Ka and attach Heart of Te Fiti to a creature
you control named Te Fiti, Mother of Mana,
then if you control a creature named Te Ka,
lose half your life, rounded down.
This is not who you are... -Moana