To double a creature's power and toughness, that creature gets +X/+Y, where X is that creature's power and Y is that creature's toughness when Unnatural Growth's ability resolves
If you were fortunate to hold onto your cards since 1999 you may want to look what cards you haveespecially Charizards
With all that being said, the top chase card from the set is mightily impressive
As someone who used to run it, I can confirm that if this card were to hit the battlefield, youd win the game that turn
Other Good Angels Outside of specialized utility Angels, there are also lots of Angels that are just really good creatures, and one of my favorites is Sublime Archangel
Blues role in the format changes a lot depending on what type of deck youre making