Fumulus, the InfestationHow it works & interactions with other cards

Converting Death into Life

Fumulus, the Infestation has two main functions: generating value from sacrifices and draining opponents during combat. The first triggered ability keys off any player sacrificing a nontoken creature, granting you a 1/1 black Insect creature token with flying. The second ability is a triggered combat ability that triggers for every Insect, Leech, Slug, or Worm you control that is declared as an attacker, causing the defending player to lose 1 life while you gain 1 life.

The Timing of the Infestation

Timing is crucial when sacrificing creatures. If you sacrifice a nontoken creature to pay the cost of a spell, Fumulus's token-generating ability goes on the stack on top of that spell and resolves first. However, if the sacrifice happens during the resolution of a spell, that spell finishes completely before the Insect token is created. Even if Fumulus itself is the creature being sacrificed, its ability will see the event and trigger one last time before it leaves the battlefield.

Strategic Deployment

To maximize Fumulus, you want to focus on 'aristocrat' strategies where you have reliable ways to sacrifice your own nontoken creatures. Because the drain ability triggers upon attacking, having a high volume of Insects—either through Fumulus's own ability or other sources—allows you to bypass traditional defenses. Since the life loss is tied to the attack trigger, it happens before blockers are even declared, often finishing off an opponent before they can mount a defense.

Interaction examples

Incremental Value with Solemn Simulacrum

Solemn Simulacrum

If you use a sacrifice outlet to sacrifice your Solemn Simulacrum while Fumulus is on the battlefield, two things happen. First, the Simulacrum's own death trigger lets you draw a card. Second, Fumulus's ability triggers because a nontoken creature was sacrificed, giving you a 1/1 Insect token. This replaces your utility creature with a flying threat immediately.

Doubling the Swarm with Roaming Throne

Roaming Throne

With Roaming Throne on the battlefield naming 'Insect', Fumulus becomes a powerhouse. When you sacrifice a nontoken creature, Fumulus triggers twice, creating two 1/1 Insect tokens instead of one. Furthermore, when Fumulus or any other Insect attacks, the Roaming Throne causes the life-drain trigger to fire twice per creature, effectively doubling the life swing against your opponent.

The Infinite Attack Cycle

Insect

Once you have established a board of Insect tokens, simply declaring them as attackers triggers Fumulus. If you attack with five 1/1 Insect tokens, the defending player loses 5 life and you gain 5 life before any damage is dealt. If those Insects are then blocked and destroyed, they do not trigger Fumulus's token ability because they are tokens, not nontoken creatures.