EastScape Wikibuilt from the game itself
Boss Bomb
“A Tinkering gadget (Tinkering 90): your next hit on a boss does 3,000 more damage. Used up when it's done.”
How to get it
- Built at Sprocket Sal's Scrap Bench: Tinkering 90, 800 scrap, 200 gears, 200 sparks, 20 relic and 20,000 tickets.