Malenia, Godess of Rot

Flying, first strike, lifelink

Infect (This creature deals damage to creatures in the
form on -1/-1 counters and to players in the form of
poison counters.)

Scarlet Aeonia — When this creature attacks for the first time, it gains trample and indestructible until
end of turn and doesn't untap during its controllers next untap step.