I suggest running the third Snapcaster Mage, as this will allow you to cast even more of those precious Red Elemental Blasts in the match ups where they matter, leading to a serious advantage in said matches
The color identity of a card is defined by all of the various symbols on the card in its casting cost, color indicator, and rules text, but does not include reminder text
However, abusing the enter ability again and again is another story
Red-Green is all about playing big, stompy creatures and other expensive spells, with extra payoffs for casting anything with a mana cost of four or higher
Urzas Saga is a land, an enchantment, a token-maker and an artifact-tutor all at once, creating a package that is difficult to ignore and hard to play against