what are some staples for a {B}{U} mill deck with {Phenax, God of Deception} as the commander
I would go with defenders. {Wall of Frost} comes to mind...
Colorless defenders with high toughness... But look at most commander mill decks and they have a few of the same items
{Mind grind} is a must
{Notion Thief} (card thief)
{Consuming Abberation}
{Mirko vosk}
{Nemesis of reason }
If you can steal creatures also : {altar of dementia}
thank you for the help
{Keening Stone}
{Mind Funeral}
{Traumatize}
{Sands of Delirium}
A ton of deathtouch and a ton of removal. Just my opinion.
Good old {Traumatize} lol
Better pack something to deal with standard (at least in my playgroup) anti-mill cards like eldrazi, elixer and others...
Among one of the new favorites is {Psychic Spiral}... So just saying to be ready to answer those if mill is your wincon.
{Doorkeeper} if you go the defender route.
{Glimpse the Unthinkable}
{Telemin Performance}
{Mind Grind}
{Mind Funeral}
Practically any Jace
{Mind Sculpt}
Possibly {Dream Twist}, but with 100 cards, it might not be worth it
{Jace's Erasure}
{Increasing Confusion}
{Trepanation Blade} if you plan on having attacking creatures
{Nephalia Drownyard}
There are lots in Ravnica, City of Guilds; Innistrad block; and Return to Ravnica block. I'd go into detail, but I've got limited internet access at work.
{Snapcaster Mage} to flashback strong mill spells
{Dralnu, Lich Lord} for more consistant flashback.