Plague Boiler

At the beginning of your upkeep, put a plague counter on this artifact.
{1}{B}{G}: Put a plague counter on this artifact or remove a plague counter from it.
When this artifact has three or more plague counters on it, sacrifice it. If you do, destroy all nonland permanents.

Plague Engineer

Deathtouch
As this creature enters, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

Engineered Plague

As this enchantment enters, choose a creature type.
All creatures of the chosen type get -1/-1.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.