Monolith

Convoke
Monolith enters the battlefield tapped.
At the beginning of your upkeep, you gain 1 life.
When Monolith enters the battlefield, sacrifice
three lands.
{t}: Add three mana of any one color.
{3},{t}: Create a 1/1 colorless Necron artifact
creature token with "This creature gets +1/+1
for each artifact you control."