During E3, it was announced by Bethesda that their modern remake of Doom was going to have a free demo of the first level for all to play and be able to test out. It would only last for a week though. However, on the official Doom Twitter account, this was said:
“Due to popular demand, we’re extending the #DOOM Demo! Download now and #FightLikeHell http://doom.com/demo”
It’s unclear at the moment whether the demo will be indefinitely free, or it will just be for a longer length of time. Regardless, this will no doubt bring some more to the modern take of the classic franchise, which many are enjoying right now.