Overlimit monsters are a new sub-catagory of Effect Monsters introduced in Limit Break of the Duelist. These monsters typically have 2 parts to their effects (the basic effect and the Overlimit, where they unlock their true power). The Overlimit effect usually require the user to have a certain amount of Life Points to use (typically 4000 or less) and must first be Overlimit Summoned. The more powerful the effect is, the more Life Points you are needed to lose in order to use them (the most powerful needs the controller to have 100 or less Life Points).
Cross Overlimit monsters
"Cross Overlimit monsters" are an evolved form of Overlimit monsters introduced in Return of the Light. These monsters can be "Cross Overlimit Summoned" in order to gain even more additional effects. To perform a Cross Overlimit Summon, however, half of the LP requirement of the original Overlimit Summon is needed. These forms of Summons do not count towards the 1 Overlimit Summon for the turn, and can be conducted even during the turn the monster is Overlimit Summoned.
- The original name of these monsters and their effects was "Limit Break".
- These monsters can be thought as similar to the Dual System, though they are not intentionally related.