I noticed that there is no mention of fireworks or explosives in the Player's Handbook.
Is there somewhere I could look for common rules and uses for fireworks/explosives in D&D 5E or previous versions? Or do I just make this stuff up with my DM?
Pages 267-268 of the 5th Edition Dungeon Master's Guide contains rules for firearms, explosives, etc. at renaissance, modern, and futuristic tech levels. No specific mention of fireworks, but you can probably work with what's already there.