Pretty much all development of ZR stalled two years ago because of other priorities. Immunity modes aren't forgotten and should be possible.
The new version is a major redesign so we will first try to get the classic game working before starting on additional features. A lot is already done (mostly by Greyscale), but a few major features are remaining before it's playable.
We haven't yet started planning how immunity modes should be implemented. It will touch several core parts in the plugin and we need to figure out an elegant integration. For certain, this feature won't go in the current stable branch.
I'm slowly catching up on development on the new version now.
Off topic: Most of the work has been development of a
framework and utilities (~12,000 lines) that will make it easier to develop features in the plugin.
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