The Reality Chip {1}{U}
Legendary Artifact Creature — Equipment Jellyfish
BlueCommander: legal
Identity
Blue
EDHREC rank
#1,081
Cheapest printing
US$4.17
TCGplayer
Printings
5
You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)
Keywords: reconfigure
Every printing
highest TCGplayer market first; a card with only a thin single listing shows its low
In short
A Commander deck is a commander and 99 other cards, one copy of each (except basic lands), all inside the commander's colour identity. Paste a full list into the deck price calculator to price it and check it against the format.