Nothing too spectacular here. Grim's mom isn't the most likable character, and her voice is kind of annoying. This was her first episode, though she would appear at least one more time in flashbacks.
Mandy is a little out of character: she screams, which is unusual (it actually freezes time), then she initially appears remorseful for doing so, before smiling of course. It's actually more of an evil grin, which I kind of miss seeing from her in the newer episodes. I know she isn't supposed to smile, but those occasional smirks served her evil persona just fine I think.
Not a hilarious episode (though Billy trying to suck up to her for the last wish was kinda funny), but worth a look.