I’ve been levelling a druid in WoW as a pacifist–basically, I don’t kill anything. (Well, except fish.) This involves a lot of sneaking, and a lot of corpse-running, and doing maybe 10% of the possible quests because there are really very few quests that don’t involve killing anything–and a bunch of those are part of chains that start with killing something, so no go there.
Pacifist levelling used to have a cap somewhere in the high 20s, because that was all the XP you could get from non-lethal questing and the token amount from exploration. These days, you can in theory go all the way to 85 on XP from gathering and, if you have Cataclysm, archaeology. Gathering from a level-appropriate node gives XP of about 1% of a level; digging up an artifact gives maybe half again as much. And since extra herb and metal nodes were introduced, it’s rarely more than a minute or so between gathers.
It’s vastly slower, though. Took me 3 and a half hours to get to level 5 as a pacifist; for a normal character it’s, what, 15 minutes? I think the slowdown is getting less as I advance in level, but it’s never going to go away completely. The upside is that two gathering professions means the character is really, really rich.
It’s kind of a neat experiment. I don’t know if I’m going to remain interested all the way to 85–I haven’t gotten that far with any other character besides Altariel anyway–but for now it’s entertaining.