This game seems like it be a ton of fun to see how long you can last with either you dieing in the end to end it or havin a option to be able to call the drop pod within a certain amount of Time or Round base style where u have the option to leave every 5 to 10 rounds or mins. Make it so the longer you stay the more enemies spawn an the difficulty spikes up as well. Bosses could have a certain time to spawn or as you progress they spawn more often. If u successfully extract depending on how long you stayed could give bonus xp, drops, resources. you could add objectives possibly during the mode but i rather just be a pure survival mode.
#Survival Mode
jagged flint
subtle oasis
I mean the newest mission SORTA lets us just kill till we feel like stoping. Not exactly the same but it’s a taste.