If Ten Numb rolls an accuracy "while attacking", and the defender scatters, does his crit ability still go off?

​I think it does, because the wording is "while attacking". So he can spend the dice and the effect goes off, before the spend defence token step where a crit effect would apply (if scatter didn't cancel the dice in the attack pool).

?

He spends the blue crit before any results are Scattered.

Scatter cancels all dice. Crits are not spent, they are triggered. So if the attack is scattered, there are no icons left to trigger the crit. This is why flotillas laugh at Gladiator I broadsides. Ten Numb's ability is great against scatter squadrons because dice are spent BEFORE defense tokens. The "while" keyword means it can only trigger once per attack.

Scatter cancels all dice. Crits are not spent, they are triggered. So if the attack is scattered, there are no icons left to trigger the crit. This is why flotillas laugh at Gladiator I broadsides. Ten Numb's ability is great against scatter squadrons because dice are spent BEFORE defense tokens. The "while" keyword means it can only trigger once per attack.

This is true for cortical effects, but Nunb is not a critical effect. His ability is a "spend" that happens to be powered by the critical icon. It's the same timing as spending accuracies, which necessarily are spent before defense tokens. It's similar to the functionality on Precision Strike, which allows you to flip cards even if the attack would be scattered.

Scatter cancels all dice. Crits are not spent, they are triggered. So if the attack is scattered, there are no icons left to trigger the crit. This is why flotillas laugh at Gladiator I broadsides. Ten Numb's ability is great against scatter squadrons because dice are spent BEFORE defense tokens. The "while" keyword means it can only trigger once per attack.

This is true for cortical effects, but Nunb is not a critical effect. His ability is a "spend" that happens to be powered by the critical icon. It's the same timing as spending accuracies, which necessarily are spent before defense tokens. It's similar to the functionality on Precision Strike, which allows you to flip cards even if the attack would be scattered.

That's what i was trying to say, but obviously not clearly. I was trying to correct Der Erlkoenig's statement while also explaining how Ten Numb's ability will be a scatter squadron slayer.

... you didn't correct my post. You agreed with my post, basically verbatim at the end.