Card Spoiler - Kaalia of the Vast

This is one of the new multicoloured legendary creatures released in the new Commander set. The first thing I noticed was her ability;

Whenever Kaalia of the Vast attacks an opponent, you may put an Angel, Demon or Dragon creature card from your hand onto the battlefield tapped and attacking that opponent.

This card to me seems fairly broken, there's quite a few high cost angel, demon or dragon cards which have silly abilities, which you can drop by turn 5 probably even 4 and be attacking. She would probably do well in a deck with mainly high mana cost creatures.
In Commander things like this will probably be fine, it's ment to be a sort of chaotic game type, but when people start including this card into regular decks it may start getting a bit silly.