Purists hate it because it used to come with a lot of weird changes, which you can turn off now (you should for a first play) and then bam, perfect Deus Ex updated for modern PCs, with great gamepad support, you didn't even have to leave Steam
Purists hate it because it used to come with a lot of weird changes, which you can turn off now (you should for a first play) and then bam, perfect Deus Ex updated for modern PCs, with great gamepad support, you didn't even have to leave Steam