Cyranon is a boss in Metroid Prime: Federation Force. It is a globe-shaped floating mechanism created by the ancient race of Bion, and is encountered in a volcanic area of the planet. The race called Cyranon its "Guardian". Its reactivation is the catalyst for M14: Tremor, where the Federation Force investigates a seismic disturbance on Bion.
Cyranon is capable of generating an outer shell of cooled magma to protect its main body. Cyranon also defends itself with Sentinels, two snake-like creatures or mechanisms that spew projectiles at the Federation Force.
To destroy Cyranon, the Federation Force must penetrate its outer magma shell by shooting parts of it off, and then targeting the inner body. It will hide in the magma until its Sentinels have been damaged enough. Both it and the Sentinels summon slow moving fireballs and rocks at the soldiers, which can be destroyed. Once the shell is damaged enough, the core can be easily destroyed. It will then sink back into the magma.
However, it will soon come back out, forming a new shell. In rising out of the magma, it creates a large wave that will cause severe damage to the soldiers if they do not jump over it. Here, the process remains the same: the soldiers must destroy the outer shell and target the core. After its second defeat, Cyranon sinks back into the magma, but then leaps out onto land. From here, it will jump, spin in the air, and then crash into the ground, damaging any soldiers it comes in contact with. Upon defeating it for a third time, Cyranon will explode.