Legendary Dragon

Legendary Dragon
Critias, Timaeus, and Hermos Critias, Timaeus, and Hermos
English	Legendary Dragons
Appears in (anime)	Yu-Gi-Oh! (Duel Monsters)

The Legendary Dragons are three ancient Knights who used to live in the Dominion of the Beasts, and answered Ironheart's call to defend Atlantis. Dartz transformed them into Dragons to weaken them. Their names come from the ancient philospher Plato's workings.

In the Waking the Dragons arc of Yu-Gi-Oh!, Yugi Muto, Joey Wheeler and Seto Kaiba each receive one of the three Legendary Dragon cards: "The Eye of Timaeus", "The Claw of Hermos" and "The Fang of Critias", respectively.

Although the Dragons are widely believed to be Spells, they were played in the Monster Card Zone in the Yu-Gi-Oh! anime.

These cards are very unique, because "The Eye of Timaeus" can fuse with other monsters to create new monsters, while "The Fang of Critias", when activated, can fuse with Trap Cards to create monsters that possess similar effects to the Trap it fuses with. By tributing another monster, "The Claw of Hermos" can fuse with it to create Equip Cards, which are then immediately equipped to a monster.

Whilst their color (blueish) indicates them to be Spell Cards, they in fact do not belong to any Game Cards list. This can be backed by the fact that they are never played face-down (hence not trap cards), they can be played whilst Spell Canceller is on the field (hence not spell cards) and they can be played during the turn a monster has been Normal Summoned (despite they are sometimes "Summoned" or "Activated") on the field.

Presumably, since they are played in the Monster Card Zones, they count towards the five monster limit of a Duelist.