Guard

Guard is a defensive move used in Paper Mario, Paper Mario: The Thousand-Year Door and Paper Mario: Sticker Star (under the name Block). It is used to reduce damage dealt by enemies. By pressing, , or just before contact, damage can be reduced by 1; the player has only 8/60 of a second before the attack connects to press the button. Guarding will also negate almost every Status Effect linked to the attack, such as Poison (the only exception is immobilization, which only one enemy in the series can perform without an item). If equipped with the Badge Damage Dodge, Guards can prevent additional points of damage. Simplifier and Unsimplifier badges will loosen or tighten the window to Guard. Guarding reduces damage even against piercing attacks.

Should an attack target both Mario and his partner, the player only has to successfully Guard the first hit; whoever gets hit second will automatically take whatever defensive action (Guard, Superguard, or neither) the first did. Because of this, there is a bug where the player cannot control what the second target does if the attack misses the first target - the second target's action will match whatever the last defensive action was for the previous attack.

In Paper Mario: The Thousand-Year Door, there exist a much stronger version of this move, called the Superguard, which will block all damage and status effects along with a small counterattack, yet requires tighter timing.

Mario & Luigi: Paper Jam has a defensive move called Emergency Block which players can use by pressing if they are having trouble performing the series' normal counter moves in a particular situation. Like in the Paper Mario games, Emergency Block can reduce damage taken by Mario, Luigi, and Paper Mario. Unlike in the Paper Mario games, it doesn't have the narrow timing to pull it off.