http://bugs.winehq.org/show_bug.cgi?id=32302
--- Comment #20 from jitsumi@gmail.com 2012-12-20 23:48:38 CST --- Apparently, Endless Space use unity 3.5.6. And apparently, from the release note of unity, unity use a mono v 2.6.3.
But they said that they fix some bug by themselves... so it is a modified version of mono 2.6.3