Here's some good news for you space marines / demon slayers that have been waiting to jump into Doom: Bethesda has retired the game's season pass, unlocking all DLC for everyone and offering free weekends so you can try the game out at no cost.
It's all thanks to patch 6.66 (I see what you did there), which (along) with the aforementioned unlocks, changes the Hack Module System to a Runes system. This drastically revamps multiplayer progression, giving players persistent perks that do not need to be activated and do not expire - unlike the modules they're replacing.
You can try the changes for yourself during the upcoming free weekend periods. The game's multiplayer, SnapMap, and first two levels of the campaign will be available to play at no cost starting at 12pm Eastern on Thursday, July 20 on Xbox One, 1pm Eastern on Thursday, July 20 on PC, and 12pm Eastern on Thursday, July 27 on PlayStation 4. Bethesda hasn't said when the free weekend period will end, but it's fairly safe to assume it'll be over once the weekend is.
And if you decide you like Doom enough to keep playing, you can buy it during these free weekends at a reduced price of $15/£12. Hot damn. Oop, pardon my language.