My current BG Rock Midrange build as of Oath of the Gatewatch (January 2016).
Ended up being 6-3 overall at Colorado's Spring SCG regionals, making 27th place. Had a diverse set of matchups, with a couple misplays, but overall it was a great deck and put up good results.
Round 1: 2-0
On the draw
Played against an interesting Grixis Control list that looked a lot like Blue moon, but he appeared to be splashing black for tasigur, Kolaghan's command, and terminates, making it like a mix of blue moon and blue jund. I feel like his deck is probably favored against BGx decks, but BG is very streamlined. After seeing him lead off with 2 basic islands I decided to try and play around blood moon and fetched my basic forest and one of my swamps. He didnt end up resolving blood moon because I inquisitioned it away. Went back and forth of him killing my creatures and me disrupting his gameplan with lili, hand disruption, and decaying his Shackles. Ended up winning with treetop village beats. Game 2 He kept a bad hand of terminate, cryptic, and 5 lands. Thoughtseized both away and quickly won with goyf.
Round 2: 2-1
On the draw
Opponent was on Jeskai Control
Kept an average hand of Goyfs, scoozes, and finks, and a decay, but no discard so it was a little rough. I played out my threats and chipped in some damage. He was able to pretty efficiently kill my guys, but struggled some with my manland. Got him to 8, but he outraced me with colonnade beats. Game 2 I boarded in fulminators, choke, and another scooze, and took out some of my spot removal. I tectonic edged one of his red sources, fulminatored another, which left him with 2 hallowed fountains and an island in play. He tapped out to play detention sphere on my liliana, and I choked him out of the game. Game 3 I stuck a t2 bob and it went unchecked for 4 draw steps and he couldnt recover. Had a similar gameplan of land destruction and he couldnt recover from it.
Round 3: 1-2
On the play
Against Naya Burn
I kept a hand of various removal, lands, and dark confidant. He mulled to 5 so I felt pretty favored. I had him fairly locked out of the game because of Liliana and other removal, but I just never drew a real threat. Played a kitchen finks on t8 or 9, but otherwise never drew a creature other than bob. Still put him to 4 by the time I died. Game two I kept a good hand of urborg and twilight mire, so I didnt have to worry about taking damage from my lands, plus I had some removal, lifegain, and good beaters. This game was pretty fast and he just couldnt keep up with the curve. Game 3 was a real nailbiter, I ended up resolving 2 kitchen finks. He tried to deflecting palm my finks, but I responded by disfiguring it, so I gained life instead of taking damage. That was probably actually a misplay because he had a grim lavamancer in play at the time, which ended up doing 8 damage throughtout the game. I put him to 1 life after killing lavamnacer and attacking with 2 finks and a small goyf, but I was at 3 and he topdecked the bolt. Was stuck on 3 lands the entire game and had a baloth in hand, which was frustrating. First loss
Round 4: 2-0
On the play
Jeskai Delver
Game one I inquisitioned his hand to see a bunch of burn, but 2 flooded strands as well, so I assumed he was on some kind of jeskai aggro build, maybe jeskai geist. Played scooze into goyf into tasigur and killed him on t5. He wrote me down as BG aggro, which I found amusing. Game 2 He played some delvers and pyros, but I played kalitas and started killing his creatures, which quickly closed out the game with zombies and the lifelinking beater. I'd say delver is a pretty easy matchup for the deck, especially post board. While fliers are annoying, we just play so much removal it's difficult for them to ride one threat to victory, like in other mathcups.
Round 5: 2-1
On the draw
Played against the monocolorless eldrazi deck for the first time, and decided that the deck was pretty good, but probably plays out similar to zoo with some explosive hands. Abrupt decay was surprisingly good here, and liliana was pretty great against everything except matter reshaper. Game one he got an early 4/4 endless one, but it didnt match up very well to 4/5 goyfs, plus removal for all his other dudes. Ended up just beating him down pretty simply. Game 2 I played a scooze and he killed it with dismember, then followed up with a surgical extratoin, costing him 6 life. I dont really know why he did that, but it worked out because I was holding 2 more scavenging ooze in my hand. That was pretty feel bad. The game carried on for a while and I got him down to 3 with some swings and manlands, but he eventually flooded out the board and I lost. Game 3 was very back and fourth, but garruk wildspeaker provided a lot of value and chumps, with an eventual overrun for the win.
Round 6: 2-1
Affinity
On the draw
Kept an okay hand of threats and disfigure, but it was a little slow. He opens with opal, 2 memnites, and signal pest. I played a swamp and passed back to him and decided to disfigure his signal pest in combat. Dont really know why I did so, but he followed up with a steel overseer post combat main phase and that overran the game. Put up a decent fight, but not having removal for the overseer screwed me. Game two I play untapped land and pass, he plays glimmervoid, ornathopter, and signal pest, then passes back. I pay 4 to dismember the signal pest, then abrupt decay his ornathopter, putting him to no permanents. Follow up with a goyf and inquistion, taking a mana source. Play 2 more goyfs and quickly win the game. Game 3 was really grindy, but I kept a hand with a lot of removal and night of soul's betrayal. Night of souls betrayal kills a lot of his remaining stuff, and he plays a master of etherium. Game stalls out for a while and eventually the board is flooded and I have a kalitas in play. He chips at me with etched champion, and then I flood the board enough that he decides he wanted to end the game before I got removal for the master. He sacs most of his board to ravager, then sacs ravager, trying to modular onto champion for perfect lethal. I get a bunch of zombies while he sacs, then he tried to modular onto his overseer. I call a judge over and have the judge explain that he cant because modular is a death trigger, but kalitas exiles it instead. This cost him 8 permanents so he conceded.
Round 7: 1-2
On the play
Played against a weird jeskai control list that was splashing black for crackling doom and tasigur. When I inquisitioned I didnt really know what he was playing, but I took a path so I could protect the goyf I had planned out for the future turns. He had a geist of saint traft, some burn, and tasigur in hand, so I assumed he was an aggressive deck. I messed up on some of my attacks and blocks because I forgot he had bolt, which ended up costing me game 1. Game 2 I boarded wrong because I thought he was some weird 4 color aggro deck, maybe even a tribal flames deck, but he was just a jeskai control list with geists and the black splash. I boarded wrong, mulled to 5, and quickly lost game 2. Still a little bummed about my mistakes in that round.
Round 8
On the play
Naya Burn
Played against one of the people I knew from my local shop, so I knew he was on burn coming into the round. My opener was a little sketchy with bob and dismember in it, but the rest of the hand was pretty good so I kept. I played bob because he was on a slow hand and it provided me a blocker and a clock if I needed one. Game was going pretty well until I flipped a liliana with bob. I got him to 4 with a lethal attack on board for next attack, but lost to his topdeck. Game 2 I had a stead stream of cheap removal and lifegain creatures, ending the game quickly. I was still at 20 at the end of the game. Game 3 he had a pretty nut draw with double swiftspear and a goblin guide, and I sequenced my land wrong, forcing me to shock myself on t3. I cleared the board with flaying tendrils, but died to his other spells on t4. I was glad it meant someone from my local shop was getting top 16 though.
Round 9, final round: 2-0
Jund
The BGx decks are actually really easy to beat as straight black green. Your mana is much easier, you have a better threat density (especially with Kalitas), and tectonic edge in the main to deal with manlands. The game still grinded out, but eventually I stuck Kalitas and killed some of his creatures, generating twice as much value for each removal. Scavenging ooze is also an all star in this matchup, usually being much bigger than goyf, and it gives you control over goyfs size.
