There is a Remastered version
here.
Mega Bomb [one-action] Feat 20Legacy Content
Additive 3 Alchemist Source Core Rulebook pg. 81 4.0Prerequisites Expanded SplashRequirements You are holding an infused alchemical bomb you crafted, with a level at least 3 lower than your advanced alchemy level.
You add an incredibly powerful additive to a held bomb to create a mega bomb, greatly increasing its area and power. You use an Interact action to throw the mega bomb, rather than Strike, and you don’t make an attack roll. The mega bomb affects creatures in a 30-foot-radius burst, centered within 60 feet of you. The bomb deals damage as if each creature were the primary target, with a basic Reflex save. On a failed save, a creature also takes any extra effects that affect a primary target (such as flat-footed from
bottled lightning). While all targets in the area take splash damage as primary targets, there is no further splash beyond that area. If your next action after creating a mega bomb isn’t an Interact action to throw it, the mega bomb denatures and loses all effects.
Traits
Additive 3: Feats with the additive trait allow you to spend actions to add special substances to bombs or elixirs. You can add only one additive to a single alchemical item, and attempting to add another spoils the item. You can typically use actions with the additive trait only when you're creating an infused alchemical item, and some can be used only with the Quick Alchemy action. The additive trait is always followed by a level, such as additive 2. An additive adds its level to the level of the alchemical item you're modifying; the result is the new level of the mixture. The mixture's item level must be no higher than your advanced alchemy level.