There are many different Secret Encounter ‘mini mission’ sections to find and locate during your adventures in Doom Eternal.
Unlike the ‘mini missions’ you get in order to obtain the Empyrean Keys, these encounters are mainly based on killing specific demons all within a certain time limit.
It can be tricky to kill these demons within the time limit too as there can be quite a few of them and some areas are rather small which means its easy to get slaughtered instead.
Anyway this page will cover how to defeat and complete the Secret Encounters that are found during Mission 6 – Arc Complex. Arc Complex has 2 Secret Encounters in total, one against a Pain Elemental, Cacodemon and an Arachnotroid, whilst the other one features Archviles and Mancubus.
The first one that you will probably encounter will be the one with the Pain Elemental and Cacodemon.
This fight isn’t too difficult, to begin with just focus on the Cacodemon and Pain Elemental and use the Ballista to take both of those out.
Once the Arachnotroid appears on the platform on the other side, simply use the Rocket Launcher for a quick and easy kill.
As for the other one that involves Archviles, though the Archviles themselves are easy enough to kill they can however turn invisible and if your not careful the secret encounter could turn into a failure due to this, it certainly did for me at least.
So to prevent this I simply lobbed a Grenade at them all which took care of most if not all of them, then I simply used whatever weapon I had invested time and effort in to defeat the Mancubus.
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