The PJ Masks didn't stop Luna Girl, her Luna Moths, and the Wolfy Kids for the first time.
The former two mainly beat the PJs to the latter by tying them into the lamppost.
As for the latter, the reason why they didn't stop them (other than being tied up) is just because they weren't doing anything to mess with the city. However, this has changed as of "Way of the Woofy" and "Moonwolfy".
Giant Lionel battles Romeo for the first time.
Lionel battles Wolf-O-Saurus along with Gekko, just like in the movie "Godzilla".
This is the third time the PJ Masks didn't transform back into their normal identities after proclaiming "PJ Masks, all shout hooray, 'cause in the night we saved the day!".
Night Ninja is the only villain not to appear in this episode.
This is the second episode that ends on a cliffhanger. At the end of the episode, Owlette says, "Now I've got a funny feeling," then Howler is shown calling for help out of the lamppost with him, Rip, and Kevin getting tickled by the moths again, so it is unknown if the PJ Masks ever came back to help them.
It appears that they did, because in "Romeocoaster", the Wolfies are shown free from the lamppost unharmed, but it is unknown how they were freed.
When The Wolfies are tied up by Luna Girl, Howler had a notch in his left ear.