Luigi

Luigi is Mario and Stefano's brother and a playable character in Super Mario Scralaxy.

Super Mario Scralaxy
Luigi appears in The Mushroom Festival as an NPC and says "Hey there, bro! Happy Mushroom Festival!" when interacted with.

Luigi later appears as a playable character after being unlocked by beating Giant Spearhead.

Luigi does a kick that gains him height when the player presses down, and his special turns him into Husk and makes him invincible for 12 seconds.