See Challenge # 116.

Mini-cycle with Sigilier of Valor and Sigilier of Heraldry. I looked for things that could be done in Bant, and one I missed was more focus on the sigils for especially prominent heros. Hence, a condition bonus mimicing exalted. I'm worried this dilutes exalted too much, maybe it should be a bonus in addition to exalted, or a larger bonus (+1/+1 counters?)

I do think it's too similar to exalted without being exalted. I think there's a reason Wizards paired exalted with lots of "quasi-exalted" abilities like that of Rafiq of the Many.

In particular, Wizards seem to have found that it works to have lots of abilities with the same trigger but different effects. Cf Battalion, Raid, Finest Hour/Battlegrace Angel/Rafiq of the Many, etc.

I could see an argument that Finest Hour, Battlegrace Angel, Rafiq and Angelic Benediction should have been in a mini-cycle themselves.

I guess, it felt to me like, once you have the idea of exalted, having an ability which partially overlaps ("when this attacks or blocks alone", or "if this is the only attacking creature, it has") it would be really confusing, but this ability is clearly built for using a single creature attacking alone, but with an extra hurdle and bigger reward.

But if it feels off to everyone else, there's probably no point trying to preserve it.

It could be exalted plus a conditional bonus, but I think it would be confusing if that bonus was +X/+X as well.

Hmm. Yes, given that the trigger is "exalted plus some other condition", I think that could work, but the bonus shouldn't be +X/+X.