Tales and Chronicles
Jewel of the North, formerly know as vincegetorix
IIRC the first playtest version of the warlock did not have spells, only invocations and their EB, much like the 3.5 one.I'd be fine just porting the 3.5 class in.
It was one of my favorite class, being the edgelord that I am. Adding the subclasses of 5e to its chassis would be awesome.