Inspired by the County song Camouflage, which has been covered by Sabaton:
The DoM battle is a lot more chaotic and ends with Harry separated from everyone else and lost in the rooms, which are a lot weirder than canon, including a big indoor forest. There are also way more Death Eaters, although most are cannon fodder rather than Bellatrix come again. Still, Harry ends up surrounded, and, after a chase through the love room, he ends up cornered. It is then that he notices a cloaked figure next to him, who calms his nerves and gives him new courage.
They fight their way through various DoM rooms, but all spells seem to go through the hooded stranger. After hours, they make it to the exit, Harry badly beaten up. When he enters the lift, he notices the stranger stands at the other side of the grate and waves back to him. That's the moment when he recognises Fleur, just as she fades away.