I'd agree with VikramS' proposal.
Here's my reasoning:
I hate Absurd and Shinobi Tradition more than Kunai. I think they are way more unbalancing. BUT, they fit their symbols better.
Efficient momentum gain without attacks dealing damage is supposed to be the primary domain of Chaos and Air. Kunai has neither symbol. Evil, Life, and Water are supposed to be relatively weak on momentum gen. They get fuel for their kills more slowly because they're supposed to champion different deck strategies.
Evil is CCHax (and similar) for good and bad: helping you make checks, hurting other folks' checks. Shinobi Tradition, while it feel it is too good (and should be at least restricted) fits on Evil.
Water is reversal fun and some card pool clearing, and somewhere along the line they decided to make it the symbol of readying your staging area (Alba, Galford, Ibuki, Billy). I think that's a dirt stupid mechanic, as it negates most of the costing in this game, but there you go. Shinobi Traditon helps you play reversals because you don't lose the resource of a ready foundation just for playing cards on your turn. It replaces card pool clearing, because it enables you to string lots of attacks together in a different way. And boy does it ready itself. So it fits on Water.
Life is the speed boost/life gain symbol. But adding one symbol that doesn't quite fit the mechanics is what distinguishes one character's support from another.
Absurd's damage boost definitely fit its Earth and Fire symbols (both damage boost symbols). It doesn't particularly fit Evil, but Evil is the wildcard there, just as Life was in Ibuki's support. I think the damage boost is too big and too easy, but there's no denying it fits two of its symbols.
Anti-momentum was never implemented enough to be really associated with a particular set of symbols, unless you count Air, Chaos, and Fire (Soul Reprisal, Unorthodox Fighting Style). Honestly, I think this SHOULD have been given to Life, which always needed something extra. Giving it to the symbols that already have momentum gain (Air/Chaos) is silly. But I guess it could fit Absurd off Fire.
I think the reason many people dislike Absurd is it does to much. Had it been split into two cards (with different symbols on each, one a damage boost, one a momentum hate), I'm not sure I would complain as vigorously about it.
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@Cetonis and da_ghetto_gamer
There's some merit to your idea of two banned lists: one very thorough to make for a much less high-powered game, one very light to let all manner of degeneracy explode. They cater to two very different ideas of "fun," but there are definitely folks out there who would go for each.