You gain the Laughing Gas Bomb formula, which doesn't count against your total number of formulas known. If you already have it, gain another formula of your choice. For you, the Bomb is improved in the following ways.
Improved Damage
All of this Bomb's damage dice are d10s.
Side-Splitter
A creature that rolls a 1 on the d20 for its saving throw against the Explode property of this Bomb has the Prone condition and its Speed is 0 until the start of your next turn.