in short, yes, but once you finish the wizardland, it's no longer playable by you in any of your games.
Do the levers in the Wizardlands do anything but summon Evil clones? I managed to summon 4 of them from 2 levers on a female character. I ran, but then I got cornered with all skills on cooldown and no escape potions. Edit: Aside from diggle hell, I think this was the only time I found levers in a wizardland. Reddit: I always thought the code got used once you entered the wizardland.
well, I'm not entirely sure, I keep notes of every wizardland I enter, and I believe Ive entered the same one a few times now, cause I was going down the list and one of the ones in the middle of my notes still worked.
Yes, not all of them summon evil clones. Spoiler The ones that are alone in a room with nothing else near them seem to always summon evil clones (And this is the most common type of lever I believe). There are others that are distinguishable from those levers though that do other things that may be beneficial. One lit up a nearby gem and which gave me a mana boost. Another appeared to do something, but for whatever reason, I didn't see anything happen. I'm not sure if there are other things that can happen, but it's possible.
I'm guessing the room with the clones is somewhat small, with (usually 2 doors) and no decoration? Kinda like the Lutefisk room except without the 9 Lutefisk(item) and the 2 sconces? Edit: or perhaps the Zorkmid room, which has 9 Zorkmid drops?
It's also worth mentioning you CAN reset Wizardlands. This can be quite handy if you lose your save via a Crash or a Bug and you used quite a few decent Wizardland codes. All you got to do is find the wkeys_all file, open it in Notepad, then delete all the text inside the file before saving it. Basically the text represents each Wizardland you have visited, and by removing them, it basically resets that Wizardland so that you can visit it again. I did this when my previous game had fell victim to a game-breaking Bug just a few days ago, found this out, and did this in order to try it again. Beat Dredmor for the first time on GRPD =D