Take a moment to let that sink in. Is the most ridiculous thing here the fact that there is a tank underworld or that it is ruled over by a particularly big tank? Or is it that your goal here is to fight that big tank with your own tank? We can’t tell you.
Presumably, those who take part in the battle to fight the tank of death will earn appropriate rewards, although the nature of those rewards is not shared in the announcement. (We can only hope you get to dress up as a zombie tank.) If all of that isn’t enough purple prose to get you interested, perhaps the actual announcement will do the trick.