Alcohol (10+beers), 50 mg benadryl, (diphenhydramine) 3 mg melatonin, 400 mg tegratol and 50 mg zoloft. What could happen?

REALLY bad idea!! Dr sangal already went through the specifics. Anyone who would be fool hardy enough to take this combination of substances either needs to see an addiction medicine specialist or a psychiatrist.
Bad idea. The alcohol would make you sleepy, then interrupt and disrupt sleep. Benadryl (diphenhydramine) will make you sleepy, as might tegretol. Zoloft might interrupt sleep. Melatonin should have little or no effect. In any case, the 10+ beers is a bad idea, with or without the other medicines.