Rod of Absorption | Echo Storm | Chromatic Orrery

Cards

Activate
Chromatic Orrery's first ability by tapping it, adding ({5} magic symbol) .
Cast
Echo Storm by paying ({5} magic symbol) , targeting
Rod of Absorption.
Echo Storm triggers, copying itself for each time you've cast your commander from the command zone this game, with each copy targeting
Chromatic Orrery.
Resolve the first copy of
Echo Storm, creating a token copy of
Chromatic Orrery.
Put the tapped
Chromatic Orrery into your graveyard due to the legend rule.
Activate the remaining
Chromatic Orrery's first ability by tapping it, adding ({5} magic symbol) .
Repeat from step 4 for each remaining copy, if applicable.
Resolve the original
Echo Storm, creating a token copy of
Rod of Absorption and exiling
Echo Storm due to
Rod of Absorption.
Activate the original
Rod of Absorption by paying ({5} magic symbol) , tapping and sacrificing it, causing you to cast
Echo Storm from exile without paying its mana cost, targeting the
Rod of Absorption token.
Repeat from step 3.
If you have cast your commander from the command zone two or more times this game, this combo nets infinite mana, and you may instead use
Chromatic Orrery's second ability to draw infinite cards and/or target any other artifact you control using
Echo Storm.