All defeated monsters (either outsmarted or killed), grant XP based on how powerful they are. Monsters begin with a base XP determined by hit dice (HD), and receive a bonus for each special ability they have (fire breath, spell-like abilities, etc.).– Labyrinth Lord, p. 49
Characters are awarded experience points (XP) for killing monsters and accumulating treasure. Monsters each have a set experience point value (given in the monster’s statistics), and each gold piece acquired earns one point as well. It may seem odd to award experience for treasure, but keep in mind that Swords & Wizardry is not just about slaying monsters – it is about outwitting your foes when you can! In fact, sometimes trickery and guile are the only way to handle a powerful monster like a dragon or a demon. Skilled players avoid risking their characters’ lives if there is another, smarter way to walk out of the dungeon with a backpack full of gems and loot.– Swords & Wizardry Complete, p. 34
Related to the Morale discussion yesterday, modern RPGs might say “defeated” instead of “killed”, but damn if it’s obvious whether they think that XP awards should include enemies who run away / break / flee / retreat / advance to the rear / exercise French discretion*. But, now that I think about it, yeah, I’m going to give some XP for routed enemies as a House Rule. That only includes enemies who have a hostile / Hostile reaction and attack, and you only get half XP, but yeah.
Way to go! You’re learning the better part of valor. The inevitable follow up for the rules lawyers is “no, you can only get ‘routed’ XP the first time an opponent runs away. After that, you can get the other half if you kill them, but that’s it. No double dipping XP farms.”.
* OK, I made that one up. I await the inevitable revenge of the French.