That's almost certainly an in-game reflection of the fact that the Mogami class were two different ships depending on when you look. They were originally built with that triple-6" armament because of some creative rules lawyering the Japanese did regarding the 1930 London Naval Treaty: Japan wasn't allowed to build new heavy cruisers, so they deliberately undergunned their next cruiser class, lowballed their overall tonnage on the paperwork, skimped a bit on some of the construction materials (that would be a problem, as it turned out), and pretended they were light cruisers. So the Mogami-class ships were designed from day one with the understanding that they would be converted into proper heavy cruisers just as soon as it was no longer diplomatically expedient for Japan to conform to the London Treaty.

That juncture came later in the '30s, at which point the underbuilding problems of the hulls were corrected and the triple 6" turrets replaced with dual-8"ers - and voilà, heavy cruisers. (Quite capable heavy cruisers, as it happened.) Hence the hull upgrade->gun upgrade path for the in-game ship.

So! In much the same way that World of Tanks doesn't model the crippling mechanical unreliability of e.g. the Porsche Tiger (which enables it to be the effective heavy tank it never managed to be in real life), World of Warships doesn't model the stability and reliability problems that Mogamin and her sisters had when they were Fake Light Cruisers - which means they work as Fairly Heavy Light Cruisers in the game, where they never really came into their own until the heavy cruiser conversion in real life. (The fact that WoWS doesn't draw an in-game distinction between light and heavy cruisers, in terms of gameplay, probably helps with that as well.)

They did a similar thing with Ishizuchi, the Tier IV premium Japanese battleship-for-game-purposes. She's fictional, but she's basically a Kongō-class battlecruiser (as opposed to the Tier V Kongō, which reflects the Kongō class after their 1930s conversions into fast battleships).

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
zgryphon at that email service Google has
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