As you walk through the last course, Bowser's Castle, as you kept walking, you saw Mario ahead, as you stood a 2 feet front of him, before you could say anything, his face gets erased, and then his arms gets extended along with his face, both his arms and his face gets way too extended to the point he becomes an tree monster, you were traumatized, and he could sense your fear to his new transformation, he looks down at you, he was just about to chase you, then he realized you're not Luigi he was waiting for, he asks

Where's Luigi? And who are you? Introduce yourself.