"Clear" (クリアー Kuriā) is an archetype of cards that were introduced in Yu-Gi-Oh! GX that were used by Yusuke Fujiwara under the possession of Nightshroud. In the anime, "Clear" monsters use the advantage of not having an Attribute while they are face-up on the field, especially while "Clear World" is activated, giving a negative effect to a player who controls a monster with an Attribute.
In Yu-Gi-Oh! GX Tag Force 3, "Clear" monsters allow users to use "Clear World" without being affected by it at all, apart from its LP cost. This allows more freedom than the anime counterparts in terms of using monsters, but the real "Clear World" is a little more forgiving with its negative effects.
"Clear World" and "Clear Vice Dragon" have been released in Limited Edition 15, making them the first members of the archetype released in the OCG. They are now released in the TCG in the pack Stardust Overdrive as secret rares. However, "Clear Vice Dragon" is still treated as a DARK monster on the field, making it vulnerable to Attribute-specific effects other than "Clear World".
One weakness you can use in the Tag Force 3 is using "Lava Golem" to Summon it to their side of the field, thus causing them to lose 2000 Life Points each turn. Another weakness to the "Clear" monsters is "DNA Transplant", which can be used to turn all the monsters into one specific Attribute and thus using the effect of "Clear World" against both players.