Cystoid

Cystoids are a type of Typhon encountered on and around Talos I during Prey (2017) and Pytheas moon base during Prey: Mooncrash.

Overview
Cystoids are the smallest Typhon creatures that the player will encounter in Prey, but their size can be deceptive. About the size of a softball, Cystoids act as mobile "mines" for the Typhon, seeking out movement and detonating violently. This explosion harms the player, and emits radiation. Cystoids can be found frequently in zero-gravity environments such as the G.U.T.S and Talos I Exterior, where they can fly effortlessly. In interior environments, Cystoids will roll around instead. They are sometimes stored inside Cystoid Nests, to be released as the player approaches, and are produced by Weavers as a defense mechanism.

Design
Cystoids look like small, black balls with spikes on them. When agitated, they glow yellow, and when they are about to detonate, they enlarge and begin to glow red.

Strategy
Cystoids kill themselves when they explode, so as long as players are aware of their surroundings, they can easily deal with them by tossing an object in their direction. Explosive canisters are effective against multiple Cystoids and Cystoid Nests.

The GLOO Cannon and Huntress Boltcaster can destroy Cystoids in one shot. In the case of the Boltcaster, Cystoids will chase the bolts and will explode if hit by one directly. This is slightly more effective in zero gravity than than in other locations, however.

A swarm of Cystoids can dish out a lot of radiation, and a large enough swarm can kill the player outright. With survival options enabled, Cystoids in the Exterior can compromise the player's oxygen supply by damaging their suit, making Cystoids much more dangerous.