The protection the sword gives means that not only can your opponent not target the creature with spells and abilities, much like Hexproof, but also means that their creatures, planeswalkers, and other permanents cannot interact with it either
When she enters the battlefield, you get to look through your library for a goblin card
It's seeing use in Greasefang decks in Pioneer as a way to bring back destroyed copies of Greasefang or get vehicles into the graveyard without relying on the randomness of drawing them
Crystal Gathering Themed Promo Foil Card x1
Tarkir: Dragonstorm's previews run through March 28, and we'll be updating this article as new cards are revealed
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