Brogue (2009)

Examining an unfamiliar creature or item is often more valuable than taking another step towards it. Stealth, fire, water and unidentified equipment make the dungeon a system to investigate, with no character build screen to solve before entering. Use the current Community Edition recommended by the original creator. Its readable descriptions help you reason about immediate threats, although a potion's appearance is not a permanent answer to memorise between runs. Patient inspection is useful from the first floor.