Rograkh in hand or in the command zone or in your library.
All other permanents on the battlefield.
You have enough mana to pay for commander tax if Rograkh is your commander.
Steps
Cast Rograkh either from your hand, from the command zone or from the top of your library by paying ({0} magic symbol) plus commander tax, if applicable.
Activate Phyrexian Altar by sacrificing Rograkh, adding one mana of any color.
When Rograkh dies, Mortuary triggers, putting Rograkh from your graveyard on top of your library.