Steam is celebrating World Environment Day by holding a massive sale that supports environmental causes.

The United Nations declared the first World Environment Day on June 5th, 1974, and for 45 years it has been used to champion environmental issues such as human overpopulation, global warming, and pollution. This year’s theme is “air pollution”, which is of particular importance to host nation China as its urban centers continue to combat smog.

It’s also a great excuse to put a bunch of video games on sale, which is exactly what Steam has done.

Although we should point out that Steam hasn’t just put games on sale for the sake of making a quick buck. A portion of all game sales that take part in the World Environment Day Sale will go towards helping environmental organizations such as Greenpeace, World Land Trust, and The Nature Conservatory.

The sale also wasn’t Valve’s idea; it was pitched by Fugi developer Johan Gjestland, whose game explores a voxel world through the eyes of a soaring bird. In keeping with the theme, the only games that are on sale are ones that feature nature in a very prominent way, such as Abzu, Staxel, ECO, Raft, Flower, and many, many more.

The sale puts games anywhere from 0 to 90% off, but most are between 15-30%. Subnautica is one such game (currently at 30% off) that you should definitely pick up as its possibly the best survival/exploration/horror game ever made. Also, 15% of their sales will go towards helping The Ocean Cleanup, an organization dedicated to removing plastic waste from the world’s oceans.

One Tree Planted has also partnered with the developers of Playne to plant one tree for every copy of the game sold on Steam.

The sale goes from now until Friday at 4 PM, PST, and is a great excuse to fill out your game collection with titles that aren’t all about killing swarms of aliens or running around in giant robots. You can have a lot of fun playing as a squirrel or a fish or a bird, and some of these games are just utterly gorgeous in their own right.

(via PC Gamer)

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