Like most comic fans, I went through a period in my life when I dropped comics completely in favor of other things (in my particular case, it was computer games). My abandonment of all things comics-related took place in the mid-1990s, which in many ways was fortunate because I missed out on many of the worst comics-related debacles, like the Spider-Man Clone Saga, the Heroes Reborn nonsense, some of the goofiest Image crap, etc. I also missed out on a period of a year or so when Marvel's UK division published original characters in comics in the United States that guest-starred traditional Marvel super heroes in pretty much every issue. All of the Marvel UK titles had either hi-tech or mystical orientations, and featured an overarching super-bad organization called Mys-Tech. I've only picked up a couple of the titles in back issue bins, and most of what I've found was bog-standard tosh,* with indecipherable plots and muddy artwork.
Black Axe was actually a little better than I expected, though the idea of an immortal, fifty-millenia-old assassin who operates in secret and carries a massive weapon (bigger than he is--look at the picture!) is inherently silly. As far as I can tell, although described as an assassin, the aforementioned Black Axe doesn't actually do much in the way of assassinating in the series, instead hiring himself out as a bodyguard so he can team up with characters like the Black Panther.
Still, the series isn't terrible and at least has coherent story-telling and average artwork. It only lasted seven issues and fans didn't even get the usual heads-up about cancellation (the last page of the last issue even has a "Next Issue:" box). As for Black Axe, as far as I can tell he's never been seen in a comic since. It boggles the mind how the cold-hearted editors at Marvel could resist for fifteen years what must be a landslide of fan letters asking them to bring the title back.
(*slang courtesy of the British Slings & Arrows Guide to Comics).