A neat little picture taken by a Dota 2 player touring the offices as part of 'The International 3 Tournament'. The picture is an International Changelog showing Valve's work on Left 4 Dead 3 and Source 2 engine.
The second picture is a zoomed in section showing Left 4 Dead 3
I would recommend IGN's site for the pictures in the source link below as they would be able to give you the high res pictures. But... is Valve finally counting to Three? Will we see some Half-Life 3 or Left 4 Dead 3 gameplay here soon? Only time will tell...
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