I love imagining how terrifying guardians are.
Imagine: You've done something wrong. Something deathly, terribly wrong - you've got a bounty on your head that a guardian's lookin' to collect for some extra cash. You're not too sure if you'll come back dead or alive, but you're not going to figure out that either, so you run. You run for days. You're exhausted, and it pursues you tirelessly.
You're scared for your life. Does this hunter ally themselves with the Vanguard, or could it care less about the vitality of a human life? It's not like it has personal experience; Guardians exist in a limbo between life and death, trampling the line that separates them with it's very existence. They hold incomprehensible power given by a god of unknown stance. Titans wear armor heavy enough to shake the earth when they walk. Warlocks hold enough knowledge to be the envy of libraries (who knows how much of that knowledge is about killing?). Hunters lerk in shadows and have unmatchable speed, and even more unmatchable stealth.
At the end of the line, backed into the wall, you grab your gun and shoot through the armor of it's skull. It takes a few bullets from the density until it falls dead. You breathe.
And then that mf comes BACK.