What SH4 editor? the S3d Editor is not made by Ubi but by the legendary Skwas. And he has already said that he will not update it for SH5.
But we do need a powerful tool for SH5 and I've been waiting for a thread to say this.
As long as the devs skillfully separate the game's engine (that they want to keep secret) apart from the submarine part of the game (AI, interface, 3d models, a few color shaders, career layers, most scripts, most controllers, etc.) they can provide us a tool with a different compiler than the dreaded Kashmir

And the mother of all modding tools is Bethesda's TES editor. The beauty of that tool is the ability to inject mods (not JSGME style). Injecting a mod means for example having different mods that change different parts the same file. Right now we need to make compatible versions of mods for other mods, even though our mods don't actually change anything over those mods, but they don't contain the changes contained in the other mods...

I hate english. Any mod made for a version of the game is at least 90% compatible with any expansion since the expansions themselves are created by the devs with that tool. Imagine having a superb collection of mods for SH5 uboats and then they would make a US expansion and all mods would become fubar...
Why would they fear giving us such a tool? Well suppose that some "fool" decides to create the American Pacific Campaign before Ubi releases an yet unannounced "SH5 Pacific War". Now... would that really happen? Did anyone manage to create an uboat in Sh4 BEFORE the Uboat Missions Expansion? I bet that for 2 whole years we'll be too busy fiddling with the uboats. SUre, we'll also cruise around with Yamatos and Bismarks, maybe even going on bombing runs with the planes

. But there's no way any mod would hurt Ubi in future expansions/games. THe only problem is that if they make SH5 as good as we want (or give us the tool to make customise it to our liking), we might not play anything else but SH5... It would hurt their other game sales

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