Ishgard, the Holy See // Faith & Grief

The adventure frame is what makes this a single slot doing two jobs instead of one, and the sequencing is where the design lives. Faith & Grief is the adventure half: five mana at sorcery speed to return up to two artifact and/or enchantment cards from your graveyard to hand. That is a substantial recursion effect, priced on the heavy side, but the adventure structure means the spell never truly leaves you. Cast it and it exiles, waiting there as Ishgard, a white source you can drop on a later turn for nothing more than a land drop. The transaction splits across time: pay the sorcery now, bank the land for later. Because an adventure hands you the spell mode without spending the land forever, both modes stay live at different points in a game rather than forcing a mutually exclusive choice at cast. The restrictions are what keep it from being pure upside: the recursion is locked to sorcery speed and to two card types, and the land enters tapped, so there is no free tempo to be had. You buy back permanents on your own clock and reclaim a mana source as the consolation prize. For a deck built around artifacts and enchantments, that is one card returning value across the whole arc of a game.