Rats summoned by Corvo do not fall under his control, although he can possess any one of them if he chooses so. As they have a mind of their own, they may attack any nearby non-player character, disposing of them in an "especially grisly manner." They will completely consume the bodies if given enough time, as would any swarm of naturally occurring rats.
When Granny Rags uses Devouring Swarm, unlike Corvo, she seems to have a degree of control over the rats—they will not attack her, and she will thank Corvo for summoning more of her "little pretties" if he uses the ability against her.
Like naturally occurring rats, the summoned rats will not attack weepers.
If Corvo is not concerned with being non-lethal, but wishes to remain unseen (min. chaos, max. stealth), he can dispatch hostiles or remove corpses by calling the rats from a high point or a hiding spot. As this power does not require Corvo to show himself to the enemy, it is one of the few offensive abilities that does not lead to automatic detection (although any remaining hostiles in the area will be on high alert afterwards).
If Corvo is not concerned with either the death score or being spotted, he can further utilize this power against mobs of enemies in the midst of combat.
The Swarm can be used for harvesting mana or adrenaline. For this to work, specific bone charms need to be equipped (Gutter Feast and Albinos for mana, Carrion Killer for adrenaline). A single tier II swarm, for instance, can recover as much as 33%-66% of Corvo’s total mana.
Tier I - (3 runes)Edit
Summons a swarm of rats which attacks and can kill and eat foes.
Tier II - (4 runes)Edit
The swarm's attacks do more damage, and it eats foes faster. It also summons more rats.
Devouring Swarm sound effect.
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|The Brigmore Witches|