Roiling Vortex

At the beginning of each player's upkeep, Roiling
Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was
spent to cast that spell, Roiling Vortex deals 5
damage to that player.
{r}: Your opponents can't gain life this turn.
I thought 'oh it's a big explosive', we'll set it off, and
it'll get us some minerals.
— Sjin