They are kind of a package deal, and dear lord, are they about to bring blue control back in a big way
In a one-on-one setting, this land is unfortunately not the greatest, as the fewer players there are, the more limited you are to what mana you can tap for, but it is handy in other formats
The first secondary commander is Rayami, First of the Fallen, who plays into the creature-exiling profit whenever the exiled creature has basically any static ability by bestowing said creatures ability onto the keyword-thirsty vampire
Using Enchantments that return to your hand anytime they go to the graveyard is a nice strategy too, as you can get back the Enchantments effect while also making sure you continue to have fuel for Ertais ability
Depending on their budget and available space, Players can usually benefit from organizing their collection by Ink Colour instead of by Set
And in a world without a functioning economy, everything is priceless