While this is technically a spoiler for the Izzet vs Golgari Duel Decks, it is assumed he will also be printed in Return to Ravnica.
Jarad, Golgari Lich Lord is a 2/2 Legendary Zombie Elf for BBGG; which doesn’t seem all that impressive. Though, his first of three abilities makes up for his low power for a 4 drop; he gets +1/+1 for each creature card in your graveyard. With the older Golgari mechanic, Dredge, he quickly becomes a monster. However, we still don’t know what the new mechanic for Golgari is going to be in Return to Ravnica.
His second ability is an activated ability for 1BG and sacrificing a creature; each opponent loses life equal to the sacrificed creature’s power. Essentially, it’s a fling to all of your opponents. If you’re playing him in Black/Green/Blue EDH, you could deal infinite damage with Grim-Grin + Gravecrawler + Rooftop Storm.
His last ability is a nice touch; you can sacrifice a swamp and a forest to return him from the graveyard to your hand. I personally don’t like sacrificing my land, but green can usually spare it with the amount of ramp.
I doubt he’ll see Standard Play when he comes out, personally; however, I expect him to see quite a bit of play in EDH/Commander, due to being a legendary creature and being a Ravnica one at that. I like him myself.
The other card I’m going to mention is Niv-Mizzet’s reprint, that I’m a little disappointed about.
As Niv-Mizzet, the Firemind is the same is ever, it’s missing one thing.
This version doesn’t have any flavor text, which I’m a little disappointed in. While the Champs one not having flavor text makes sense, it doesn’t even have the alternate flavor text shown in From the Vault: Dragons.
I’ll get to Niv-Mizzet in my Generally Speaking series when I get to him.