Love customising mechs and going into battle? Granvir: Zero Front is a new prologue, acting as a long-term demo for the bigger game of Granvir that's due out later. Seems to be worth a look if you love mech action. It's now available on Steam, it's free and has Native Linux support.
Save data from this will also carry over to the full game whenever it releases.

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I'm a bit of a sucker for games like this, no doubt I'll be spending quite a few hours in it building my mech. Like a nice cross between Mech Warrior and Armored Core.
More about it:
Granvir: Zero Front is a third person shooter action roguelite featuring mech building. Experience the prelude to the Millennium Horizon campaign in Granvir as the first resistance response to the Millenium Company invasion. Players battle through a route of their choice reaching extraction and completing side objectives at the cost of valuable resources. Between battles, players can swap out parts for upgrades found on the battlefield and manage their campaign by taking on loans to afford ammunition, aiding the locals for support in battle and more.
No campaign is the same as you manage time, resources and your route to each objective. Each zone impacts what services and resources are available. Use down time between missions to refit and upgrade your Granvir to prevail.
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