Trashtron

When Trashtron enters the battlefield, place
+1/+1 counters on it equal to the amount of
recycled mana used to cast it.
Trashtron's base power is equal to the amount of
Trash Pile tokens you control.
If Trashtron would leave the battlefield, put X
1/2 colourless Trash Pile Creature tokens onto
the battlefield with "Sacrifice this creature: Add
1 mana of any colour to your mana pool." where
X was it's power on the field, then exile
Trashtron.