Artistry of Corrosion

Myr you control get +1/+1 and have
"{t}, put a -1/-1 counter on this creature: Add
one mana of any colour.
Post Mortem: At the beginning of your upkeep, sacrifice all noncreature artifacts you control.
(When This card's owner loses the game, if there are
at least two more players, each player gets an emblem
with "At the beginning of your upkeep, sacrifice all noncreature artifacts you control.")