Embercleave only technically costs that much because of its ability: it costs one less for each attacking creature you control
Sunfall Sunfall from March of the Machine was the last truly pushed white wrath we've seen
The payoff of this meld pair, doesn't win the game on the spot, and I'd stress that to your Bracket 3 playgroup because while this deck puts together powerful cards, it is not optimized to be unbeatable, and more focused on a huge play with some Golgari death and graveyard interaction molded in
Rodriguez also got into character for the film, recently revealing the difficulty she had with losing muscle mass since bulking up to play a Barbarian
It's not as much of a jump as you get by Shifting a card, but it also doesn't rely on having specific cards in play and in your hand
The mana value restriction of 4 also represents that it is a basic item for reviving your party members, not a miraculous Lazarus stone