Cloud Climber is a free walking sim about exploring surreal towers
Learn a bit about the end of humanity while you're at it.
Cloud Climber is a nice way to spend fifteen minutes of your day, I think: A surreal walking simulator about exploring the environment of three massive towers, each stretching towards the sky to reach the clouds. It's a fully voiced game with a nice, hand-drawn graphical style and casual gameplay, where mostly you just wander about, climb stairs, turn cranks, and lay planks. Classic video game stuff, really.
As you explore the clouds you're treated to voiceover narration about why the towers were built and why you're climbing them—the surface of earth no longer has water, and you're going to the clouds to get it. That's also why there's nobody else around. Overall, it's a simple game, but a delightful and quite pretty one. It's sitting at 91% positive reviews on Steam, where it's free to download.
Two Star Games is a one-person indie studio that also made free puzzle adventure game My Friend is a Raven. Its current project is My Beautiful Paper Smile, a rather terrifying looking horror game about a "a child who is raised in a facility to wear a smile forever." Both Cloud Climber and My Friend is a Raven are also available on Itch.io.