From Lexicanum

The Multi-melta is a heavy version of the Meltagun that has multiple melta barrels. It is an ideal anti-tank weapon, especially at close range. It is a vicious and effective weapon, but lacks the range of other heavy weapons. In different sources, melta weapons are described as firing with either a blinding flash, and emitting a beam of light, or just projecting a nearly invisible beam of intense heat. Targets are just melted away - turning creatures into pools of steaming protoplasm and vehicles into twisted goo. No personal armor offers even scant protection from a multi-melta.

Multi-meltas can be mounted on vehicles. It has the same characteristics as a Meltagun but has a much increased range. The Leman Russ Demolisher may have sponson mounted Multi-meltas and the Land Raider Crusader has a hull mounted Multi-melta. The Immolator may have twin-linked multi-meltas. They also may be mounted on Land Speeders (and their variants), Attack Bikes, Razorbacks, and Dreadnoughts.

Given the bulky nature of these weapons, they are only man portable by Space Marines, Chaos Space Marines, and Sisters of Battle, and even then they carry vast and bulky power packs on their backs. Only the human armies (including the Imperial Guard) use Multi-meltas as other races have their own versions.

Images

Sister of Battle with Multi-Melta

A Salamanders Space Marine with Multi-Melta

Known Multi-Melta Patterns

• Maxima Pattern (used by the Astartes)

Sources

• Codex: Space Marines (4th Edition)
• Codex: Dark Angels (4th Edition)
• Codex: Chaos Space Marines (3rd Edition, 1st Codex)
• Codex: Imperial Guard (3rd Edition, 1st Codex)
• Codex: Witch Hunters (3rd Edition)

Melta Weapons

Imperium	Inferno Pistol • Meltagun • Multi-melta
Eldar	Fire Pike • Fusion Gun • Fusion Pistol
Tau	Fusion Blaster