High and Score use twin based magic in their fight, so focus on one at a time. Score is best to take out first as he can revive High. If you take too long Raistlin will wake up and start throwing wrenches at you.

You can find rohypnol in the abandoned warehouse. Marshall Banana has the key, and you must find her in the Strawberry Hotel to get her to open the door. During the mission there is a secret requirement that if done will prompt her to join your party. She is a Samurai with White magic, and is usefull i the High and score battle.