Amethyst, Wolf of the Night

At the beginning of each upkeep, if no spells
were cast last turn, put two +1/+1 counters
on Amethyst.
Whenever a player casts their second spell each
turn, remove a +1/+1 counter from Amethyst.
If you did, draw a card.
{b}{g}, Discard a card: Amethyst gains hexproof
and menace until end of turn.