Venir, The Mage Of Poison

When Venir enters the battlefield, put a -1/-1 counter on all other creatures.
{b}{b}: Destroy target creature with a -1/-1 counter on it.
When Venir dies create a token that is a copy of him except it is now a poison elemental in addition to its other types.
Venir deals damage in -1/-1 counters to creatures.
"I will defeat Azoth to prove my strength!"