I really couldn't decide whether this would go in general or rules, but since it's a question about whether something is usable or not I guess it's more rules. So forgive me if my reasoning is poor.

Question is quite simple, as they've been released at an event, are the new ATA's legal to use in modern?

This is the general rule for when things become legal:

WES - Tourney Resources

Legal Game Elements: Any Modern Age game elements that have been officially released for more than 1 week are legal for this tournament.

http://win.wizkids.com/bb/viewtopic....d3614d10a6bded

Purple?

...

I thought it might be a good idea to switch from Orange. I wanted to create a little separation from the Oranges before us who were official WK Deputies and our role which is different. I was also hoping to avoid any perceived arrogance on our part as we refilled the ranks. Thanks BigSoph and Rowdy.

I really appreciate normalview, Harpua, Quebster, and Vlad who are all very helpful and supportive. Furthermore, I want to continue to thank many of the other people who continue to contribute to the rules discussion who have an expertise bit arent highlighted with a color.

i like the purple

thanks for the clarification Icehot, and the purple is nice

Ooooo, we're purple now. The fade is a nice touch, too.

So picked a colour favoured by the Emperors of Rome

Only joking guys the new colour looks cool especially with the fade effect.
All hail the mighty purples.