Zack Snyder’s Justice League: 27 WTF Moments
8. The Dead Wonder Woman Premonition
When Cyborg and The Flash activate the Mother Box in order to bring Superman back, Cyborg mentions that the Mother Box is telling him not to wake it, at which point he witnesses a vision of a potential future in which Darkseid triumphs over the League.
The disturbing sequence includes numerous horrifying sights: a very dead Wonder Woman on a funeral pyre with coins over her eyes (presumably to pay her fare into the Underworld), Darkseid murdering Aquaman, Black Suit Superman cradling a skeleton he may or may not have melted with his heat vision, and holding what appears to be Batman's mask, possibly containing his head.
As a nod towards the evil Superman arc which may have happened in Justice League 2, it's a fascinatingly grim tease of the Mother Box's dark potential.