Did some testing, and did not notice any “cascade” issues, but did notice a significant difference with gem converters (like Justice). So I think this is probably the issue console players have been reporting which causes the excessive looping, it’s cause has just been misplaced. @Mithran’s post above is a really good description, so I won’t restate all of those points again, other than a quick comment on the converters.
I can confirm this, after doing a bunch of test battles with Justice on PC and comparing to mobile. However, the Sirrian post @Mithran links to is more related to the AI (which reportedly has not yet been changed for unity), and I think the issue is more related to the “overwriting” Alpheon describes in Nimhain's Lair: June 12th - #135 by Alpheon . Because the Unity code doesn’t overwrite the same colour the way it did in the previous (or current mobile) code, a lot more gems are converted. Obviously “a lot” is relative, but my testing showed it to normally be an extra 3-4 gems. While only a few gems, it seems to be the tipping point, where “normal” boards seem to align extra turns at least half the time, and partially primed boards almost all the time. Note that this occurs for both the player and the AI, it seems to be a change in the mechanics rather than the AI.
And based on that, adding in a slightly smarter AI who can’t always be baited and whose colour preferences can be tweaked (coming “soon”), as well as the inability to nerf your opponents with weaker defences (seems to be live on PC, but not on mobile), and the game is going to become much more challenging.