From the Super Mario Wiki
Retrieved from "https://www.mariowiki.com/index.php?title=DEF-Up&oldid=2784758"
DEF-Up is a positive status condition that has appeared in several Mario RPGs. It stands for "Defense-Up".
Mario & Luigi series
Mario & Luigi: Superstar Saga / Mario & Luigi: Superstar Saga + Bowser's Minions
Green Peppers boost defense (and gives the Light G effect) in Mario & Luigi: Superstar Saga and Mario & Luigi: Superstar Saga + Bowser's Minions, meaning enemy attacks will do less damage to Mario and Luigi. The status is indicated by a gray box with an arrow pointing up next to the Mario brother's HP.
Mario & Luigi: Partners in Time
Green Peppers appear again in Mario & Luigi: Partners in Time, although they both affect all fighters that are currently active, and no longer causes Light G. DEF-Up is indicated by an expanding green circle around the attacker.
Mario & Luigi: Bowser's Inside Story / Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
DEF-Up makes another appearance in Mario & Luigi: Bowser's Inside Story and its 3DS remake, Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey. Green streaks flowing upward indicate the affected, and in the remake, the affected turning a green color. Def Peps can give this status effect to other enemies. Bowser can gain this status by inhaling a Toothy's body segments and a Crawful's teeth.
Mario & Luigi: Dream Team
DEF-Up reappears in Mario & Luigi: Dream Team. Green streaks flowing upward and green flashing indicate the affected. By using a Bronze-Guard Badge combo, Mario and Luigi can increase their defense. During Kamek's third battle, his green copy can raise the defense of the real Kamek and the other copies.
Mario & Luigi: Paper Jam
Paper Mario: The Thousand-Year Door
In Paper Mario: The Thousand-Year Door, several items and the Crystal Star power called Power Lift can raise defense. The DEF-Up status is indicated by a gray diamond with an arrow pointing up above Mario or his partner. Enemies can also receive this status effect.