Most Overlooked PC Game?

What do you the most overlooked PC game is? I would vote for RO2/Rising Storm, or Sanctum 2. 

Any genre or DRM platform is allowed (uplay, Desura, Steam, etc.).

vampire masquerade - bloodlines

Shadow Warrior, Planetside 2, Toribash

Section 8: Prejudice (assuming multi-platform is okay)

civ 1 2 3 and 4

 

How are those overlooked, especially since some consider 4 to be the best in the series?

I agree. Planetside 2 is really fun, but you need to join up with a group because running solo sucks really bad.

empire earth

Dust an elysian tale

I second this with an addition of Valdis Story

The game that got me into PC gaming!

Yup, oldie but a goodie.

Outcast. That game was awesome

A couple of smaller games I never see anyone speak of that I found amazing were Superbrothers: Sword & Sworcery, and Megabyte punch.

At the moment I would say Insurgency its a great game but not a ton of people play it.

Total annihilation, I never understood how a game so good and groundbreaking was so ignored

The S.T.A.L.K.E.R. series

I agree with RO2/RS. Another one could be Natural Selection 2.

Yes. This game is great, but gets no attention.

Wizardry 8 A bit dated now but still amazing. The company went broke at publish time so it never made it mainstream.