From the MTGS thread found here: http://www.mtgsalvation.com/forums/the-game/commander-edh/multiplayer-commander-decklists/217212-grand-arbiter-augustin-iv-the-prison

Potential Changes:


Completed Changes:
8/5/15
OUT: Brainstorm
IN: Polluted Delta
OUT: Isochron Scepter
IN: Sapphire Medallion
OUT: Memory Lapse
IN: Copy Artifact
OUT: Dream Cache
IN: Jace's Sanctum
8/19/15
OUT: Wall of Denial
IN: Monastery Mentor
OUT: Halimar Depths
IN: Prairie Stream
OUT: Jace's Sanctum
IN: Frozen Aether (better control card)