DO NOT USE, EVEN IF CREDITED AND/OR ASKED! This is my take. Ok on to info. Phase 1: Papyrus is wary but still wants to spare you. If you spare he will accept. But gaster will kill you when you proceed. Phase 2: Yea, no mercy. He is angry and would use harder attacks.(Duh) Phase 2.5s: Gaster is taking over his body while talking to the player. Yes, YOU. Phase 2.75: His body becomes covered in static. The reason is, there can only be one non-existent entity. Since papyrus has gained so much LOVE, he is considered a new semi-entity but, he is no longer fully recognized by the game, in term, sending him to the void. Gaster explains this to papyrus. Phase 3: The game has some recollection of gaster before sending him to the void. He has some attacks like hands, bones, blasters. Since papyrus isn't fully deleted to the void, and his soul is being controlled by gaster, AND gaster is less stable than papyrus. His stats slowly become papyrus's stats. In term, making him have stats again. Phase 3.5: Gaster now has 0.5 HP and is too unstable to be out of the void. He gets forced back into the void and papyrus becomes normal. Phase 4: Due to having part of gaster in him(Due to him controlling him) he can block with gaster hands and is more powerful. When the first hand breaks, part of the crack heals, and he becomes weaker because the hands are part of gaster. When the second hand breaks, gaster is once again stable in the void. And returns. Phase 4: Gaster rips papyrus's head off draining his magic to allow him into the body and soul. This allows him to become semi-stable. He doesn't take damage due to him not fully existing like last time. You need to destroy papyrus's body to destroy him.
Original Sprites by Papyron95. Edited by me.
