Semmes is a very tall and massive individual, towering in both height and mass over his fellow teammates for the Grand Magic Games, distinguished by an outlandish appearance. Topping his very wide, mildly rounded torso, standing on a pair of rather stocky legs and possessing muscular arms ending in large hands, is his head, which has only the face visible, this being rounded as well, notably small in comparison to the rest of Semmes' body, and strangely colored: two white semicircles are located at its sides, each going from the eye to the corresponding side, while the central part is light blue in color. Semmes' eyes don't have visible pupils, being completely white.
Covering most of Semmes' large upper body is a single black garment, even extending up to his head and acting as an hood of sort, leaving only his face exposed, and growing a pair of prominent protrusions jutting outwards from the sides of the head, each ending in a large, golden sphere. The collar circling the area where Semmes' neck is supposed to be is also golden in color, while a large, light decoration shaped like the letter "X" adorns the central part of such cloth. The hood seems to be detachable from the shirt part, as shown from Semmes wearing it, minus the golden collar, even while bathing in Ryuzetsu Land. On his legs, Semmes wears a light, mildly loose pair of pants reaching down below his knees, possessing prominent hems and coming with a sash circling his waist and bearing a similarly colored waistguard split in two parts, with each part hanging above the outer side of a leg. His feet are covered by dark shoes with light soles, which on the upper part bear a light "X" not unlike that adorning his shirt, though way smaller.
Grand Magic Games arc
Semmes and his team participate in X791's Grand Magic Games, competing in the preliminary event "Sky Labyrinth" and completing the latter in 7th place, being thus admitted to the real tournament, with him bearing the guild's banner. The group cheers Yaeger up as the Mage volunteers himself for the Hidden event, and similarly encourages War Cry as he readies to battle Sabertooth's Orga Nanagear, with their comrade's instantaneous defeat at the hands of Orga's Black Lightning leaving his teammates blank.
Semmes is shown crying out in enthusiasm with the rest of his comrades as Bacchus, who took over War Cry due to the latter's injuries, comes in 1st place during the Chariot event, earning them 10 points. During Bacchus' battle with Team Fairy Tail A's Elfman Strauss, the group beholds the power of the S-Class Mage and his visible advantage over the opponent in joy, but are left in a state of comedic dismay when Elfman, as part of his bet with Bacchus, states that his victory will change the name of their guild in "Quatro Puppy" for the rest of the Games; something which comes real with the unexpected defeat of Bacchus, much to their still comedic astonishment.
When the third day's battle portion starts, Semmes is chosen to fight against Team Mermaid Heel's Millianna, having been defeated easily after being bound by her tubes.
On the third day's evening, Semmes is present in the Ryuzetsu Land water park alongside the rest of his team, relaxing in a pool while repeating his guild's signature phrase. The evening, however, is brought to an abrupt end by Natsu Dragneel, who accidentally destroys the water park with his Fire Dragon Slayer Magic, leaving everyone on the ground, with Semmes resting below the Fairy Tail Mage Cana Alberona, who was socializing with the Quatro Cerberus members.
In the Event part of the Fourth Day, Semmes' teammate Rocker is sent to the event as the only male in the competition, that involves knocking out the competitors of a giant water sphere. Rocker is quickly the first to be defeated, receiving a massive foot stomp from Blue Pegasus's Jenny Realight, much to the shock and embarrassment of Semmes and his teammates.
In Volume 32's extra content, Mashima provided the battle statistics for 31 of the 40 X791 contestants in the Grand Magic Games. The stats, however, were provided not from Mashima's point-of-view as the author but from the view point of Sorcerer Magazine reporter Jason. Which explains why some stats are missing and why others may be inaccurate. According to Jason from the Sorcerer Magazine, during his participation in the Grand Magic Games of X791, Semmes's stats are: