Doom Wiki
For the grenades in Strife, see Explosive Grenade and Phosphorous Grenade.
For the grenades in Doom (2016), see Frag Grenade and Siphon Grenade.

"The infantry issue fragmentation grenade is activated by a twist detonator. Fire delay is 3 seconds, with an injury radius of 30 meters."
PDA Description [src]

Grenade is a weapon in Doom 3. They can be found for the first time in the Administration level inside the code locker near the entrance and in the communication room.

Combat analysis

A blueprint of the Grenade.

It is an explosive weapon that deals splash damage, damaging anyone in the vicinity, including the user. Despite being shown in 4 canisters, Grenades actually come in a set of 5. It can bounce off walls but will explode on contact with the intended target. Grenades can also be cooked, allowing it to be thrown farther. However, a time limit is set. If cooked for too long, it will explode in the user's hand, killing him.

Tactical analysis

Grenades work best when an enemy is positioned in a corner where the player cannot shoot them. This works best against Z-Secs, as they have the tendency to take cover and hide. It can also be used to earn a quick kill on unsuspecting enemies, particularly if they enter through doors. Enemies such as Imps, Maggots and Tentacle Commandos will die if hit by one. It can also kill multiple Zombies with one explosion.

Grenades are also useful against Revenants before obtaining the Rocket Launcher because they deal a similar amount of damage as the Rocket Launcher. However, they will require two grenades to be taken down. Slow moving enemies such as Mancubi are also effective.

A major problem of grenades is that they can bounce off from walls and objects. If there are lot of obstacles in the way, the player should exercise great caution to ensure that the grenade does not hit any stray objects in the area, thus letting it bounce back towards the player before exploding, hurting him.

If you can maintain your timing well, you can also utilize on cooking the grenade to take out enemies from further range or if they are lurking far off in a corner. As the weapon instantly explodes in contact with an enemy, it is crucial to maintain distance from them due to the weapon's splash damage.