Type-3 Antipersonnel/Antimatériel Incendiary grenade

"It sure don't seem like it was meant for burnin' material, seems more like it was meant for burnin' personnel."

- Anonymous E2-BAG/1/7 serviceman

The Type-3 Antipersonnel/Antimateriel Incendiary Grenade, colloquially known as the "Firebomb," or "Flame Grenade," is a Brute grenade.

It is a multi-purposed infantry explosives munition and can be thrown 10 meters (32.8 feet) by the average soldier. Upon impact with a hard surface, the casing converts to liquid form, burning at 2200 °C (3992 °F) and causing significant damage to vehicles and infantry alike, automatically killing all nearby infantry in a 3.4 meter (8 foot) radius. The gel-like filler substance also escapes from the burning casing, splashing over nearby objects and causing significant damage as it burns for 4.5 seconds. Killing someone in multiplayer with this grenade will award the player with the Incineration Medal. In campaign, it's a very effective weapon against the Flood. It should be noted that if you get hit with a Firebomb Grenade in the legs, if you quickly run into the river in Valhalla or the sea on Last Resort you will survive.

Quotes
The following are observations of the Type-3 Incendiary Grenade from servicemen of the UNSC Marine Corps unit E2-BAG/1/7.

"The filler seems to be a liquid or a gel or something; it dissipates pretty rapidly under water—I don't know how it would behave in hard vacuum."

"It doesn't burn under water, unless it's already on something and burning. A "thermite", otherwise heat, grenade will burn under water and that crap has been around forever. Hey, is it just me or does Brute tech seem to be all over the map? Either there's no info sharing on Brutonia or something bad happened."

"Baby Kongs use 'em exclusively as AP grenades. Kongs tend to capture or abandon material more often than they deny it."

"None of the other alien foxtrots use 'em. Either the bravo kilos don't trust 'em with 'em or the rest of 'em ain't as keen on burnin' folk as kilos are."

Trivia

 * Created by the Brutes during the Covenant Civil War in hopes of retaking High Charity.
 * The Firebomb is the rarest grenade in Halo 3.
 * The Firebomb is one of two Brute-manufactured grenades in Halo 3. The other being the Spike Grenade.
 * Even though Incendiary Grenade is the proper name, it is referred to as the Firebomb Grenade in the game (likely because it is listed as the Firebomb Grenade in Forge).
 * The only time it appears in the Halo 3 campaign is in The Ark, The Covenant, Cortana and Halo.
 * It does not appear by default on any Multiplayer map, nor does it regenerate using the "Grenade regeneration" option. They are only available if they have been previously added in Forge.
 * Only Brute Stalkers use incendiary grenades in The Halo 3 campaign. Killing Brute Stalkers is also your main source of these grenades.
 * Turning on the Halo 3 Skulls will make all Brute Stalkers drop two firebomb grenades, making it easier to obtain the grenades.
 * It is wasteful to use these grenades on anything except Chieftains and perhaps large, dangerous packs of Brutes due to their rarity and extreme power.
 * The Incendiary Grenade will kill any Chieftain in a single throw on almost any difficulty except Legendary, as long the Chieftain gets the bulk of the explosion, spreading the fire all along the body, not just the limbs. It is a guaranteed kill unless the Chieftain activates an Invincibility power-up.
 * One Incendiary Grenade can kill up to three Flood Combat Forms or Flood Pure Forms in a close group. They are also useful against large swarms of Flood Infection Forms. When stuck to a Flood Carrier Form, the resulting fire will burn thoroughly and not release any Flood Infection Forms from the Carrier. This proves the weapon very effective against the Flood.
 * The Firebomb can kill any player with one throw in Custom games, burning them as they move.
 * This is sometimes referred to as a "cheap instant flamethrower" by players.
 * It can be used to create a "wall of fire", burning those who chose to cross it, restricting enemy movement in the area. Very useful in skirmish games such as Assault, CTF, etc.
 * Like all other grenades, it can be shot mid-air and detonated by a weapon fire.
 * It can't be used in a Warthog Jump so don't try it.
 * If thrown into a Warthog passenger seat at the proper angle, it will get stuck, like the Frag Grenade, and bounce.
 * There is a glitch where no fire appears, but your opponent still dies.
 * The likely reason for not appearing in Multiplayer is because of frame rate or possibly balance issues.
 * Players sometimes refer to the Incendiary Grenade with names such as, "Anti-Water Balloon", "Satan's Grenade", "Lava Can", and/or "The Cocktail".
 * The Incendiary Grenade looks in someways like the head of a Spike Grenade with a reactor in it.
 * Even though it is a brute grenade they are almost never seen using them.