RBT is pretty much best used in combination with Gits and Flames.
Gifts any attack doing 4-6 damage, Flames in Phase 0 of your next turn removing all of their units, Bolter them with any remaining resources then do it again after you claim your resources during the Kingdom phase. Ideally you want to make sure that you can do at least 23 damage which will kill them unless they have developments or damage mitigation.
In my experience this works best in a ridiculously defensive HE deck splashed with dwarf for Master Rune and lots of support orientated resource generation. My current version is almost unitless, having only 3 Dragonmages for use with defend Tor Aedris as an extra method of defence. Essentially you have to try and slow down your opponent long enough to set up your kill.
Unfortunately in the current rush environment it is far from being sufficiently reliable enough.
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