Diffusion Missile

The Diffusion Missile spreads a shockwave outward. These four "snowflake" shapes rapidly spin and expand around a central point.

Diffusion Missiles (ディフュージョンミサイル Difyūjon Misairu) are a special type of chargeable Missile made by the Galactic Federation. They further increase the damage of missiles, and when fully charged, missile impacts release four snowflakes that swirl outward spanning the entire screen; freezing enemies, opening nearby doors, and destroying both Shot Blocks and Missile Blocks. Their only appearance is in Metroid Fusion, and they are the fifteenth item collected by Samus.

Properties

At first, Adam reacts with feigned surprise that Samus acquired the upgrade, stating that it had not received a report from HQ that the upgrade had been sent and it was likely a procedural error. It later states that the Federation was in fact trying to withhold this weapon from Samus, because they feared she would grow too powerful in her attempts of annihilating the X Parasites. However, they already sent it and she found it, accessing it from Sector 4's Data Room.

They do not use up any more Missiles than would be normally used, even when charged. Whether charged or not, the Diffusion Missile is more powerful than the standard Ice Missile, dealing 12.5% more damage (from 40 to 45), 50% more damage than a Super Missile, and 350% more damage than a Normal Missile. An enemy that takes three Ice Missiles to kill will generally only take two Diffusion Missiles. It is readily noticeable that the Diffusion Missile launches are much more explosive and powerful than the standard Ice Missiles, seeming to create a visual difference between the two. Once Samus gets the upgrade, the aspect of her missiles will change and they will resemble Super Metroid's Super Missiles.

This upgrade is similar to the Special Charge Beam Attacks for the Ice Beam in Super Metroid, as both the Ice Beam's attack and the Diffusion Missiles spread a sheet of ice that freeze anything it comes in contact with. It is also similar to the Ice Spreader in Metroid Prime.

In Metroid: Other M and Metroid Dread, there is a beam upgrade called the Diffusion Beam that disperses bursts of energy from a charge shot similarly. Diffusion Missiles do not return in Dread, the sequel to Fusion.

Official Data

Metroid Fusion manual

DIFFUSION

"Fire Diffusion Missiles while charged to release a powerful blast that damages enemies within a certain radius. Press and hold the R Button then fire the Missiles when charged up."

Metroid Fusion in-game acquisition message

"Diffusion added to Missiles.
Charge with [R], fire with [B]."

Metroid Fusion: The Official Nintendo Player's Guide

DIFFUSION MISSILE

"Diffusion Missiles can power up, much like the Charge Beam. Press and hold the R Button to charge a Diffusion Missile, then press B to launch it when it's at full power. The Missile's detonation will destroy or freeze all of the X parasites within a wide blast radius. It's the perfect weapon for dealing with large groups of enemies in a hurry.
Charge up a Diffusion Missile then aim it into the middle of a group of enemies.
The Missile's blast will destroy or freeze every enemy within its range.
Location - Sector 4"

Metroid Prime and Metroid Fusion: Prima's Official Strategy Guide

Diffusion Missile

Location - Sector 4

Acquired By - Data download

Controls - Hold [R] until charged, then tap [B]

"This weapon is a lifesaver, especially when a squad of Rippers blocks your path. One shot freezes everything within the blast radius. A Diffusion Missile is the answer against inflatable bombs that block Samus's path every time she approaches. Wait until the bombs are deflated, then freeze them with a Diffusion Missile, allowing Samus to walk or roll by."

Trivia

The debug menu label for Diffusion Missiles is "CLUSTE", short for "CLUSTER," like several other shortened names. This is the only one that is inaccurate, however.

• When an uncharged Diffusion Missile hits a wall and Samus grabs a ledge, she is still able to hang on. However, when a charged Diffusion Missile hits a wall, it knocks Samus off the ledge, similar to how the Power Bombs and Super Missiles force Samus to let go.
• It should be worth noting that the Manual for Metroid Fusion states that the charge damages enemies within its radius. This is actually false, as it simply freezes all enemies within its radius (that can be frozen by the blast). Enemies will only receive damage from direct contact with a Missile shot, regardless if charged or not.
• In the Debug Menu of Metroid Fusion, the Diffusion Missiles are listed as CLUSTE (short for Cluster), implying that the upgrade may have originally been named Cluster Missiles.
  • When equipped exclusively, Diffusion Missiles function the same as usual.