Potion of Invisibility
Potion, rare · 2024 rules, SRD 5.2
This potion's container looks empty but feels as though it holds liquid. When you drink the potion, you have the Invisible condition for 1 hour. The effect ends early if you make an attack roll, deal damage, or cast a spell.
Also in the 2014 rules (SRD 5.1).