The appeal of an event comic to Marvel or DC is obvious. It acts as a publisher’s tip of the spear, giving the whole effort focus and the rest of your titles something to push up against and to connect to, furthering the idea of the shared universe. That allows a publisher to say that exhibit A – the event comic – is important, and through transitive properties, exhibit B – the regular titles that tie-in – must also be important.

When it delivers, it works for everyone. This year’s House of X and Powers of X – two titles that formed one event – are an example of this being done well. It’s undeniable that Jonathan Hickman, Pepe Larraz, R.B. Silva and friends created a whole lot of excitement with their work on those two stories that were one, and from there, the fervor for the world of mutants carried over to the Dawn of X line. Perhaps it’s a bit dialed back, but the heat is still there, with each week’s release still generating plenty of conversation.

But when done poorly, there can be a cost there. While an effort like House of X and Powers of X amplified interest in the X-Men line as a whole, creating a positive area of effect in the following titles, an event that misses the mark can cause a commensurate chill on connected books. Momentum can be lost, interest can wane, and for little to no gain. That can be a problem.

And it’s one that DC Comics is looking at now the conclusion of Event Leviathan, as this six-issue event from Brian Michael Bendis and Alex Maleev managed to rip defeat from the jaws of victory while compromising my interest in the larger world of Superman stories in the process. That’s not exactly what you’re looking for from an event comic, but therein lies the risk of betting big on one.