The fact that the final ability only saves your attacking creatures unfortunately caps its potential
We realized that every time we had ever put it in a non-core expansion, we had changed the card in some way, and it seemed only right to finally let Giant Spider visit a new plane
the one that required breeding a Gold Chocobo and finding that hidden island
Where the real power lies, though, is with Sphinxs activated ability
Cryptic: The focus of the classic Space Hulk game that pits elite Space Marines against these purpose bred hunters, Genestealers are excellent and terrifying infiltration units, serving as the forerunners of Tyranid invasions
Pair it with something that removes -1/-1 counters or adds +1/+1 counters when it comes into play and a free sacrifice outlet like Ashnod's Altar and this creature goes infinite in so many ways