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Phyrexian Scriptures and Elspeth's Nightmare provide card advantage and removal while upping the deck's enchantment count
Seal from Existence's last ability creates two one-shot effects: one that exiles the permanent when the ability resolves, and another that returns the exiled card to the battlefield immediately after Seal from Existence leaves the battlefield
Perhaps the clearest ancestor is Retrace, the paradigm mechanic for repeatedly casting spells out of the graveyard (unlike Flashback and Unearth, which only work once)
The commander damage is also reduced from 21 to 18, and you're able to use your commanders abilities from the command zone with a tax applying for every time you use them after the first one
The two are still completely separate properties, even if they do bleed into each other from time to time