Please watch the episode with any necessary subtitles before discussing: Crunchyroll / Daisuki / FUNimation
Also, please make sure to follow the Kanzenshuu Forum Rules. You may wish to review examples of unwelcome posts, as well.
-------------------------------
General Discussion for Dragon Ball Super Episode 120, aired 17 December 2017

完璧なる生存戦略!第3宇宙脅威の刺客!!
Kanpeki naru Seizon Senryaku! Dai 3 Uchū Kyōi no Shikaku! !
A Perfect Survival Strategy! Universe 3's Menacing Assassins!!
Summary:
The Omni-Kings review the current status of the tournament, seeing that many warriors have been eliminated and only three universes now remain. Though the tournament will soon be over, the Great Priest assures them that the truly exciting part is still ahead, now that only the top warriors from each universe remain. Following the loss of Piccolo, there are now only six members left on the Universe 7 team. Goku is certain that Jiren and co. over in Universe 11 will be their final opponents, but out in the bleachers Piccolo thinks they shouldn’t overlook Universe 3.
Indeed, at that moment the U3 God of Destruction Mosco declares (via his angel, who serves as interpreter) that with so few warriors remaining, now is the perfect time for them to finally get serious. Following Mosco’s orders, Paparoni assembles the other four remaining U3 warriors, and together they go after the U7 team. While 17 and 18 struggles against Viara (whose defense ranks near the top of U3), Vegeta finds that Bollarator can anticipate his movements thanks to Koitsukai’s analysis. Whis can tell that their team won’t have such an easy time defeating warriors who have managed to survive for this long.
Continuing to analyze the U7 team from afar, Koitsukai directs Panchia and Bollarator to defeat Goku and Vegeta with coordinated attacks. But Gohan protects Goku and Vegeta from the U3 warriors; he’s determined to take out these opponents on his own, so that Goku and Vegeta can conserve their stamina. Gohan manages well against Koitsukai, Panchia, and Bollarator, anticipating their movements much as they did with Vegeta.
Meanwhile, 17 and 18 use their infinite stamina to gradually wear down Viara’s defenses with an endless barrage of ki blasts. Viara collapses after cracks form in his armor, and 18 knocks him out of bounds. With only four U3 warriors left, Mosco commands them to begin “Plan X”. At Paparoni’s instructions, Koitsukai, Panchia, and Bollarator merge together into “Koichiarator”. The U3 Kaioshin Ea explains how Paparoni modified those three so that they could combine into this, the ultimate warrior.
Observing events from afar, Toppo thinks that U3 has been keeping a rather troublesome ace-in-the-hole, while Freeza looks forward to watching how things play out. Gohan’s initial barrage of ki blasts has no effect on Kochiarator, who despite his large size proves to also be faster than before. As Gohan struggles to block one of Kochiarator’s attacks, Goku and Vegeta suddenly rush in and knock Kochiarator away. Goku assures Gohan that thanks to him, he has recovered his stamina.
Goku and Vegeta go Super Saiyan Blue, and for a time their blasts manage to push Kochiarator back, but with Paparoni’s encouragement Kochiarator manages to counter their blasts in the end. Paparoni declares victory, but in fact Goku and Vegeta were merely buying time so that Gohan could charge up an attack of his own. Now that they’ve created an opening, Gohan nails Kochiarator with a Kamehameha that eventually breaks through the merged warrior’s guard.
It seems that Gohan has defeated the U3 team, and Beerus is so impressed that he finally calls Gohan by name. Though Kochiarator is nowhere in sight, Paparoni has managed to remain in the arena. As Gohan and co. go to drop him out of bounds, he vows to unleash U3’s true final tactic, and Kochiarator suddenly appears behind him…
10 minutes remain in the Tournament of Power.