Not always. Every group I played with back in the 90s use a combo of 2e and AD&D (1e). But the unofficial "2.5" was pretty much incompatible with 1e.
Or runequest. Staid true since 1978ish. With some weirdness 2002-2017 which i know little about. Encounters, spells etc all perfectly comprehensible. Skillnames and such having shifted a bit.
Last edited by Raze; 14/03/22 12:29 PM. Reason: deleted forum account
