Plague Behemoth

Defender, Outlast{w}{b}{t} : ({w}{b}{t}:Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
When this creature dies, put X Plague vial artifact tokens onto the field with "Sacrifice this artifact: put a -1/-1 counter on target creature.", where X is the number of +1/+1 counters on this creature.