Bo unleashing her true powers when the lich threatened Lauren was a rather terrifying version.
Trick's backstory where he forced a peace between dark and light fae by writing their peace accords in his own blood.
Trick popping up behind the hunter of a body swapping Fae, and knocking him out with a little sleep dust.
Trick: Try to lock me up in my own lair...
Kenzi showing up with a chainsaw to deal with the Norn. Made all the better by the normally arrogant old hag going from her usual cackling to pure terror.
And before that, The Garuda uses his powers to cause in an internal fight between Bo's team. Kenzi uses the distraction to sneak around The Garuda and hit him In the Back with her club. It doesn't work, mind you, but she gets points for trying.
Kenzie, juiced up on a sticky staff, wiping the floor with a whole room of Pig Men Fae.
Lauren of all people punching out Vex. And earlier, her finally getting sick of Kenzi's crap and calling her on it.
Hale telling off The Morrigan for her unlawful attack on the Light.
Bo being Genre Savvy enough to figure out that Kenzi behaving strangely and her stories not meshing with Lauren's is a red flag, but still waiting for definitive evidence before calling it out, just in case.
Bo: You like that, bestie? *referring to the noodles Kenzi has just eaten*
"Kenzi": Mmm! They are so good.
Bo: *SLAMS her up against a column by the throat* And covered in peanuts, which you are deathly allergic to. So tell me, bitch—where the hell is Kenzi?
Tamsin displaying her Fae powers for the first time in "The Kenzi Scale". She actually makes Dyson back away in total fear.
And she didn't actually do a thing, just looked super scary.
Dyson winning his forced cagefight in "Hail, Hale" by ripping his opponents throat out..
Dyson, Trick, and Tamsin holding off the armies of the damned.
Bo, with help from Lauren, killing Massimo.
Bo warns that Lauren that her ability to turn Fae into humans will have them all gunning for her. And Lauren's response is a dead-cool "Let 'em try." It's not even confidence that Bo will protect her, it's confidence that she can handle it.