I spoke with a developer of ANTRAXX [Official Site, Kickstarter] a little while ago when they were considering full Linux support, now they have launched their Kickstarter for their online mech battler and Linux is a go.
Mechs are apparently customizable with collectable parts and weapons, it also has a map editor.
It has a handy in-browser demo, but sadly it doesn't let me play. Every time I click a game it just disconnects me which is a shame. I was hoping to write a few brief thoughts on this one. This is the same issue I told them I had back in July, so it's a shame to see it still not fixed months later when their Kickstarter has launched, doesn't fill me with a lot of confidence.
If I'm going to be honest as I can, It's hard to write anything interesting about a crowdfunding game when a demo is offered that hasn't worked for 3+ months.
The developers are looking to get €30,000 and they have a long way to go, but hopefully this fun looking mech shooter will prevail.