Agatha of the Vile Cauldron (WOE 199)

Legendary Creature — Human Warlock • Mana cost: {R}{G} • Wilds of Eldraine • Mythic

Activated abilities of creatures you control cost {X} less to activate, where X is Agatha's power. This effect can't reduce the mana in that cost to less than one mana.
{4}{R}{G}: Other creatures you control get +1/+1 and gain trample and haste until end of turn.

Illustrated by Jason A. Engle.