On Halo Episode 10
lightsabers are just deadly glowsticks, yeah. while star wars lightsabers use stupid soft science that doesn't make sense, I've seen a video of the realest possible lightsaber you can get: big hot glowstick, connected up to a big battery to power it, and its real dangerous, and basically just a 1000 degree knife on a bigger scale, anything it touches it slices through not because its sharp or anything, but because its burns and melts through it. glows orange. like unless there something revolutionary is figured out to store large amounts of energy in smaller packages, thats probably the closest we're gonna get.

maybe the needler's spikes turn blue when a human holds it?

ah yes Luke's father, its Han Solo right? right there all along. but it could be Bib Fortunata,

Yea the Flood was well executed in their introduction and how they are presented. it turned a shooter game with two sides into one with three sides, when normally you don't get much more complex than a single monolithic faction or type of enemies, and despite the Flood being arguably the worse of the two enemies, they managed to play with the dynamic in interesting ways and not have it be an immediate team up against the newly discovered threat.