Omnath, Totem of Stones

Trample
As long as Omnath, Totem of Stones is
in play, all lands you control are colorless and
produce colorless mana.
Omnath, Totem of Stones gets +1/+1 for each colorless mana in your mana pool.
Mana doesn't empty at the end of each
phase.
When Omnath, Totem of Stones is in play all
spells you cast and control are colorless.