Action DooM! Easter Egg - The Doom-guy's Stuff - Hissy, Daisy, and a 'Smarch Calender'.

On the ship to Phobos, (Use idclev4 to save time) you take a pile of your belongings with you. There are many references here most people don't even understand, so I will try and explain a few.

One of the first things you will notice is the little rabbit jumping around your feet. This is meant to be a reference to 'Daisy' from original DooM. The actuel Doomguy from the original DooM had a pet rabbit named Daisy, who died at the end of episode three.

Also, take notice of the tiny stuffed Cacodemon (A monster from the original DooM) sitting on the sofa. This is a reference to the DooM community's own 'Hissy'. Hissy was a little stuffed Cacodemon plushy who was sent from Doomer to Doomer in real life. She became famous when there was a huge protest when one man failed to continue the cycle.

"Free Hissy!!"

You will also notice a calender on the wall titled "Smarch". This is also a very deep easter egg.
In Treehouse of Horror VI of The Simpsons (A popular Cartoon show), Groundskeeper Willie haunted the children of Springfield Elementary in their sleep. This was found to have been caused by his death in the school furnace, on the 13th hour of the 13th day of 'The thirteenth month' which was, indeed, Smarch (Due to misprinted calenders.) His death happened, ironicly, during a school meeting on the subject of misprinted calenders.