{Descendants' Path} {Haunted crossroads}
And if you aren't running a specific themed deck like just elves, {conspiracy}. I also like having {Into the wilds} out too.
Scenario: Sliver Deck
In play: descendants path, haunted crossroads, into the wilds, and a sliver creature.
During your upkeep look at the top card for a land, if it's a land put it in play. Then look at the top card for a creature, say it is a sliver creature, put it in play. Draw a card.
Say someone kills off your sliver, use haunted crossroads to put it on top and put it in play on your upkeep.