Easily one of my favourite places to nerd out at. And DEFINITELY my favourite place to nerd out at in the GTA.
Legends has extremely competitive pricing (Games Workshop stuff usually 20% off!) and a very nice selection of board games, comic books, cards, minatures, and geeky merch (I definitely picked up a Rainbow Dash mug on my last visit here.) If they don't have something that you have your eye on, you can connect with them to see if they will order it for you (which they likely will, if they can!)
Really flexible hours of operation, open late many nights of the week, and there are constantly events occuring here. They have a fairly large, well-lit, and clean gaming space in the back.
Customer service here is quite friendly. I'd HIGHLY reccomend checking out Legends if you are in/around the Vaughan area to get your geek on :).