Sans had been starting to come to as Papyrus shook him, but the loud explosions caused by the Mother's blasters startle him the rest of the way. He teleports a slight distance off of Papyrus's back as he wakes up, promptly landing on his back.

He looks in the direction of the sound, sockets wide as he scrambles to sit up. He has no idea how he got here.

"What the hey...?