Vincent Lemoine was the more experienced player in this semifinals, with Top 8s at Grand Prix Athens 2006 and Pro Tour Paris 2011 to his name. His opponent, Damien Bouillot, was playing in his first Grand Prix Top 8.
Judging by the decks that they drafted, the two players had different perspectives on the Limited format. Bouilot avoided green and assembled a good version of what many consider to be one of the best archetypes in Battle for Zendikar Limited: Blue/Black Ingest. His best opening would be Culling Drone into Wasteland Strangler.
Lemoine, on the other side of the table, went against the common wisdom. While most players tried to avoid green, Lemoine actually liked the color and drafted a green converge deck with Prism Array, Tajuru Stalwart, Exert Influence, Roilmage's Trick, and Skyrider Elf. He had two Sylvan Scrying for fixing along with a remarkable toolbox of eight different nonbasic lands, many of which feature enters-the-battlefield triggers.
The turning point was Murk Strider. It allowed Bouillot to add a relevant threat to the board while taking out the biggest blocker on Lemoine's side, all in the same turn. Lemoine still had a bunch of sweet cards like Prism Array, Roilmage's Trick, and Exert Influence in his hand, which would have been great if the game went long, but he could only play one card per turn and found himself too far behind on tempo.
In the subsequent turns, Bouillot kept matching Lemoine's plays one-for-one and rode his early board advantage to victory.
Damien Bouillot 1 - Vincent Lemoine 0
But an Exert Influence from Lemoine (cast off of his motley assortment of lands including Lumbering Falls, Canopy Vista, and Fertile Thicket) swung the game hugely in his favor as he took control of Cloud Manta. This way, he not only took out an important attacker, but also gained a way to trade with Malakir Familiar.
Bouillot's draw just didn't come together in this game, as evidenced by a non-processed Mind Raker and a Tide Drifter that didn't do much to improve his board state. Ultimately, Lemoine's more powerful cards took over the game: he set up the one-two punch of Rush of Ice plus Sheer Drop to destroy an opposing blocker, leaving himself with two extra 3/3 attackers, and swung in for lethal.
Damien Bouillot 1 - Vincent Lemoine 1
Bouillot didn't have a fast start, as he only added two Culling Drones and a Coralhelm Guide to his board over the course of the first five turns. Lemoine, in the meantime, had played Blisterpod, Snapping Gnarlid, two Call the Scions, and Oran-Rief Invoker.
So it looked like we were in for an unusual game of Battle for Zendikar Limited in which the only creatures on the battlefield were 1/1s, 2/1s, or 2/2s, especially after Lemoine's plans of eventually playing Eldrazi Devastator were foiled by Mire's Malice.
We were now in topdeck mode. Lemoine's deck coughed up Sylvan Scrying, to the hilarity of the Belgian crowd, who had been very much amused by Lemoine's unusual land toolbox. Looking through his deck, he found Lumbering Falls, which admittedly wasn't bad, but it wasn't enough to change the tide of the game.
The most important card on Bouillot's side of the board, as it turned out, was Coralhelm Guide. It first made Culling Drone unblockable to enable the processor ability on Wasteland Strangler. It then pushed his creatures past the Lumbering Falls. And eventually it was sacrificed to Smothering Abomination for value. Several turns later, Bouillot attacked for lethal.
Damien Bouillot 2 - Vincent Lemoine 1