To be honest, I'm not the biggest fan of Tesla. He can be funny in small doses, but I don't think I'd be able to stand him for over an hour. Because "Trail of Blood" is a Tesla episode and his presence is accentuated, I can't say it amused me that much.
But the plot, revisiting a Cabal lab where the vampire source blood got mixed with bugs, was cool enough to keep the episode going. Tesla's somewhat noble sacrifice, or at least his attempt, was a good way to bring back that slightly non-selfish character who rears his head once in a while.
Likewise, the Kate and Bigfoot tracking down the killer of a priest who once helped Bigfoot was surprisingly heartfelt. It was a little short though, but we'll be revisiting the plot later to find out who the hooded faux-priest is.
Will's "I told you so" lines got tedious about the third time, and Will became a useless pest by the end of the episode. Why does Will have constantly remind Magnus that Tesla has ulterior motives. Magnus knows it and the audience knows it, and repeating it 20 times won't change a thing.
I looks like the two second opening credits is here to stay. Sigh...
Score: 8.6/10