Henge of Ritestones

{t}: Add one mana of any color.
{t}, Sacrifice X creatures: Add X colorless mana.
{b/r}{t}: If a black or red spell was cast this turn,
deal 3 damage to any target.
{g/w}{t}: If a creature entered the battlefield this
turn, gain 4 life.
{u/r}{u/b}{u}{t}: If a blue instant or sorcery was cast
this turn, copy it. You may choose a new target
for the copy.