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Casting elemental nova when you are despecialized (or if you take one of each element) always seems to give you the same order of runes (Fire > Ice > Lightning), regardless of what the actual result of the cast is. If you specialize into one specific element, you will always get that element first. If you specialize into two elements, it will still follow the same order (I.E if you took Fire and Ice it will always be FIFIFIFI while Ice and Lightning will be ILILILIL).

I was kind of hoping to get more of a russian roulette style where the rune you get matches the exact element you managed to get, but it might have been too chaotic. Maybe it could be a unique in the future that shuffles the order for spells that can be multiple elements like E Nova and Disintegrate.

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about 1 year ago - /u/ehg_trasochi - Direct link

If a spell has multiple elemental damage type tags it'll always give you the rune you gained least recently, or default to Fire > Cold > Lightning to break ties. We felt this would give players the most control over gaining the runes they needed with multi-elemental skills.

There are nodes in the Runebolt tree that randomise the order of the combo or directly randomise your runes. Those might provide the sort of chaotic feel that you're looking for.