Divine Convocation is all about flooding the battlefield with creatures as quickly as possible, and it's very good at doing that
As this doesn't find any of the good red cheat in effects you typically only see this in the Reanimate / Shallow grave lists and those both being black mean this is very much a backup card
However, its so strong offensively that some people actively avoid casting it as protection since it lets an attacking army juke out any blockers while granting them double strike and lifelink
In reference to this fact, Nurikabe's artwork depicts Gyarados rising out of the ocean, clearly enraged and preparing to unleash a powerful Hyper Beam on those who dare to disturb it
And if MH1, and MH2 are any guide, that will be more than enough
That can win the game quickly with your Isshin's and your copy makers like the Resonator