Ymir, Father of Frost Giants

Defender
Whenever another creature enters the battlefield
under your control, you
may pay {s}, If you do create a 0/2 ice wall creature
token with defender
{s}{s}, sacrifice up to 5 ice wall's and make a legendary
Frost Hammer equipment token and attach it
to Ymir. Frost Hammer gets Trample and +2/+0
for each ice wall sacrificed to make it and Ymir can
attack as though he didn't have Defender