It's pretty much a 0/8 for 4, which is pretty "meh". It can save other creatures too I guess, but I can see this being used on itself more often than not. Well, maybe not. I saves things from Lightning Bolts and the dreaded Karplusan Wolverine, so maybe it's not as bad as it first seems. Still, it's a 0/4 for 4 otherwise, which isn't that great.
Pros: Can save a creature from damage
Cons: 0/4 Wall for 4