X-Men: Dark Phoenix - 21 Easter Eggs & References Explained

3. The MCU Gag?

When Jean's powers are shown to their full extent, the peace between humans and mutants quickly falls apart and we hear reference to a mutant prison, which is clearly a reference to the Ice Box prison sited in Canada, which also appears in Deadpool 2 after first appearing in the comics. Later, we see similar power Inhibitor collars used in Deadpool 2 and from the comics too.

Linked is a strange little gag that could well be a purposeful nod to Marvel and the Disney/Fox deal. When the mutants are being transported to the prison, the troops brought in to transport them wear patches with MCU on their sleeves. Clearly, it means something like Mutant Containment Unit, but what's curious about it is that a group already exists in Fox's universe with the same job but a different title.

In Deadpool 2, we meet the DMC, but then they wouldn't have given us the tongue-in-cheek sight of the MCU being blown up.