Doomtrain

Doomtrain (Japanese: グラシャラボラス Gurasyaraborasu (Glasya-Labolas); French: Helltrain) is a summon appearing only in Final Fantasy VIII, as a Guardian Force. Its attack, Runaway Train, is Poison-based and can inflict several abnormal statuses on the enemy, with Sleep, Poison, Darkness, Silence, Slow, Stop, Berserk and Vit 0 being the complete list, thus being vastly helpful against the majority of bosses. Runaway Train 138Tqvwas2g Abilities learned from Doomtrain are listed below:

Obtaining Doomtrain
To obtain Doomtrain, you need the Solomon Ring, 6 Steel Pipes, 6 Remedy+, and 6 Marlboro Tentacles. Once you have all of these items, use Solomon's Ring, and Doomtrain will join you. This can first be accomplished on disc 3.

Solomon's Ring can be found on Tear's Point, Steel pipes can be mugged from Wendigos, Remedy+ can be obtained by refining 10 Remedy's with Alexander's Med-Lv Up ability, and Marlboro Tentacles by defeating or mugging Marlboro's

When the Solomon's Ring is used, Doomtrain will call out: 'You called upon me?' 'I am...' (at which point the player names the GF) 'I shall become your ally'

Reference
Doomtrain resembles, and some have speculated that it may have been inspired by, the Phantom Train boss in Final Fantasy VI. Besides the obvious similarities in name and appearance, the two also have the same power to inflict many detrimental status ailments on enemies.