Shield Sphere - 0 (yes 0)
Artifact Creature - Wall (Alliances U2)
0/6. (Walls can't attack.) ; Whenever ~this~ blocks, put a -0/-1 counter on it
So it costs 0, meaning that it is very Affinity friendly.
It makes negative tokens, meaning that it is very Power Conduit friendly.
Power Conduit is a casual behemoth! Ack! Hans Run!