I think Harvester is better in a Mono Black deck because black is limited in ways to destroy non-creatures and has many ways to get value out of your own creatures dying, but if you're in, say, black/green and packing lots of green's artifact/enchantment removal, Kothophed could be superior
It also features several ways to copy lands (Vesuva, Copy Land) to artificially up the town count
There are some three drop mutants in standard at the moment, and adding 'when this creature dies, draw at least two cards' makes even the worst of them playable
(You descended if a permanent card was put into your graveyard from anywhere.) Legendary Artifact The Aetherspark As long as The Aetherspark is attached to a creature, The Aetherspark can't be attacked and has "Whenever equipped creature deals combat damage during your turn, put that many loyalty counters on The Aetherspark." +1: Attach The Aetherspark to up to one target creature you control
So if you want a Sliver deck that focuses on beating face, then Sliver Swarm is the deck for you