Kicking it oldskool with the ToEE.

[lesser_minion]

THAC0 didn't exist - you had to look up what to roll on a table.

The counter-intuitive AC bit was still there though.

Rounds are one minute long, broken into segments. You act once per round, and everyone on a particular side acts in the same segment. Spells have a casting time measured in segments, which is pretty much all that happens in the last four.

You can read OSRIC for a rough guide to how everything worked. I'm guessing the combat tables were a little different, however.

IIRC, most experience tables worked out as being a case of "you need X amount of XP to hit second level", and from then on the experience total needed to gain a level doubled.

The core classes were: Assasin, Bard (really weird appendix thing that gets druid spells, fighter bonus attacks and a pile of other weirdness), Cleric, Druid, Fighter, Ranger, Paladin, Theif, Monk, Magic User, Illusionist. I think that covers all of them.

I skipped over 2e, so I wouldn't be able to give you a perfect comparison, although I think 2e made Bard into a real class and removed Monk.

OSRIC link: http://www.knights-n-knaves.com/osric/