World Tree Saproling

Whenever a land enters the battlefield, put a
+1/+1 counter on each creature land on the battlefield.
Your commander gets +1/+1 for each creature
land on the battlefield.
{t}: Put three +1/+1 counters on target
noncreature land. Untap it. It becomes a 0/0 Elemental creature that's still a land. Its
controller may choose to ignore this ability.