Potion of Possibility

A Potion of Possibility is a potion containing a clear (or grayish) shining substance that halts somewhere between liquid and gas in its form. Its drinker gains two Fragments of Possibility.

Properties
Each Fragment of Possibility looks like a tiny, grayish bead of energy that follows you around, staying within 1 foot of you at all times. Each fragment lasts for 8 hours or until used. While you have one or more Fragments of Possibility from this potion, you can't gain another Fragment of Possibility from any source.

When you make an attack roll, an ability check, or a saving throw, you can expend your fragment to roll an additional d20 and choose which of the d20s to use. Alternatively, when an attack roll is made against you, you can expend your fragment to roll a d20 and choose which of the d20s to use, the one you rolled or the one the attacker rolled. If the original d20 roll has advantage or disadvantage, you roll your d20 after advantage or disadvantage has been applied to the original roll.

Cerberus Assembly Research
During their study, the Cerberus Assembly hired Yeza Brenatto in Felderwin to attempt to extract the power of the dunamantic field from a Luxon beacon and distill it into a potion for military purposes. His experiments resulted in large areas of people, surrounding the apothecary he worked in, to feel sluggish or move at unnaturally fast speeds. Yeza eventually was able to distill a single vial of dunamis power and there were plans to make more, even considering the costly and time-consuming process.

Campaign 3: Bells Hells
In and before 843 PD, the Cerberus Assembly was shipping their crates to the Paragon's Call in Bassuras, with at least two of the crates containing six Potions of Possibility spread among them. Additionally, the leader of the Paragon's Call, Otohan Thull, had two contraptions on her back filled with dunamantic liquid from these potions.

Several years before 843 PD, Ashton and the rest of the Nobodies broke into Jiana Hexum's home in Jrusar as part of a job. Jiana walked in on the attempted burglary and used magic to push Ashton back. They fell out the window and were gravely injured when Milo Krook found them. In their hand, Ashton clenched a glass vial that looked like a potion of possibility.