Targeting the opponent can be upside in some spots, but a liability in others, and on the whole, Id call it a wash
Surge of Salvation Although its slightly skewed against black and red, Surge of Salvation is very efficient at a single mana, and the hexproof isnt limited to those two colors, either
III Other creatures you control get +2/+2 and gain Trample until end of turn
Since the dislocation happens between the stack and the graveyard , it isnt the triggering event for Rancors third ability, so it doesnt trigger
The unique fun is in doubling every payoff from death, turning attrition into a win condition
It's just a lot of fun, and I run Arachnogenesis in decks right now