Stardew Valley is really lightweight and Linux native.
Since you mentioned battery being an issue and that you just switched to Linux, have you looked into using TLP or Powertop to try doing some tweaks to squeeze out a bit more? It's been years since I've used Linux on a laptop, but that's what I used.
Seconding OpenMW! Don't let the upcoming release being unfinished dissuade you from playing! I played through the whole game back in 2015 with OpenMW on a crappy laptop with about as many bugs as is normal for a Bethesda game.
The did great work to get it to that point back then, and I'm sure it's even better now.
Tumblr itself still exists and is active. Redditors from some of the more LGBT and lefty subs have left for Tumblr too