They are not useable again until they are readied again through an action or game rule, and are vulnerable to being challenged
What's especially nice about Faithful Mending is that its flashback cost is relatively cheap, and it provides you with all important life gain to stave off aggressive decks
While Eidolon has a creature version of Pyrostatic Pillar, a powerful burn card in its own right, Cemetery Gatekeeper is like a more flexible creature version of Ankh of Mishra
I look forward to casting a big ol' Genesis Wave and then drawing 5+ cards for my troubles
But, unlike Ephemerate, I think the equipment is part of such a strong and game-winning combo , that it deserves a high spot on our list
Grand Crescendo is ideal for this because it has the protection spell mode, but if you draw it after the board wipe, it helps you rebuild whereas something like Heroic Intervention only works reactively