For me Spelunky is an instanope, something about the controls just feels completely off and nothing about the game makes me want to play long enough to get used to it. I just tried again and for a second time decided to quit before finishing the tutorial. I can't agree here. I only played Trine 2 (and quite some time ago), but I didn't like it at all and have avoided the series since. I remember feeling relieved to get to the end and be done. I don't remember the details but I don't think I got used to the mechanics, (maybe relatedly) didn't find the level design interesting, and the narration might have been nice if the story was better. IIRC, the nice unusual thing about the narration is that it would react to your actions more directly than any other game I've played (also providing hints after a while unless you change a setting).

The one game I can highly recommend in this sale is Guacamelee (as someone who likes platformers and doesn't play fighting games). I've only played the first one so far (and only single player) but it sounds like the second is fairly similar. It is my favorite platformer. It gets quite difficult but there are checkpoints at least every other screen. The music is excellent although like almost all games is too repetitive. Other platformers I like (not in the sale) include Hollow Knight, Little Bug, Beatbuddy, the old SNES Dokey Kong Country games, and the A Valley Without Wind games.

I did (Humble Bundle DRM-free version so possibly not exactly the same as on GOG) and I didn't like that one either, although the thing that really ruined it for me was fairly minor: I found the "inhabiting random people's bodies to teleport" thing really creepy (also indicating a not very coherent story where that is possible but surveillance is fairly limited). I didn't play all that far (or that recently) so I can't give much other info.

100% agree. Also, that ghost... 50% agree. Although the visuals are remarkable (and I generally do not care about shiny graphics) and the general atmosphere is fairytale-y, the use of realistic physics in the gameplay sucks. Numerous times I struggled trying to place those magical cube things correctly. Personal opinion of course. That's the reason I abandoned Trine 2 after completing the 1st one.

edit: Also, any opinions on Outbuddies DX and Chasm? They both have interesting discounts right now.

Could also try Reddit, or uhm.. the GOG forum. I found one of my best gaming buddies after making a post on Reddit looking for players.

I was wondering this myself. I own Trine 1, 2, 3. But not 4. 4's not on sale at all except as part of the bundle. Annoying.