From Halopedia, the Halo wiki
Infusion grenades are filled with infusion gel. They can be thrown by grenadiers or launched from specialised grenade launchers.
The infusion grenades were created following the creation of the infusion gel by Voridus.
Infusion Grenades are used by Brute Grenadiers in the the campaign of Halo Wars 2: Awakening the Nightmare and can be used in PvP multiplayer & Blitz for Voridus players.
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