The Codrex, Spirit's Pulse

The Codrex, Spirit's Pulse enters the battlefield
tapped. It does not untap during your untap step.
{c}, Sacrifice an artifact creature you control:
Untap The Codrex.
{t} : Add {w}{u}{b}{r}{g}.
"In the world that feeds the world, of course. The wellspring of flame that blazes bright, yet burns none
but its bearer. And he, oh, he it burns until there is
nothing left, not even ashes." - The Builder