Cards that genuinely take advantage of this are few and far between, so your best use of Serras Sanctum would simply be to put it in an enchantress deck.
Lotus Cobra, for example features the elegant flower on its hood
Brawl Legal Vintage Legal Timeless Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Legal Their mind whirled with grand plans, never thinking of what might happen if they got to the end of the list.
Generally, Dragons Rage Channeler[/card] is such a strong card because of the following 2 aspects: On the one side, its a 1 mana 3/3 flyer which gets to play an aggressive game plan for Rx tempo and midrange decks
But yeah, Doctor #4 has a once-per-turn effect that lets you play historic cards (that's to say, legendary cards, artifacts, and sagas) from the top
The existence of strong free spells like Mishras Bauble only makes the card more reliable in Modern and Legacy, too