Let me know in the comments or, er, hop on over to the Draftsim Discord
It's unlikely Biophagus will see play in decks where counters don't matter, but he's a great addition to the many decks where they do
For singles, theres always sites like Amazon (you can also get other cards like Pokemon or Yu-Gi-Oh
Sheoldred is more exciting as top end goes, Grave Titan packs a lot more punch for the mana and things like Shriekmaw and Kalitas are far more preferable in any sort of midrange affair simply because they are relevant in the game that much sooner
Better sleeve it up! kind of thing
The two sides strengthen each other, blending nostalgia, creativity, and investment