While Dragon Ball Super and Dragon Ball GT as both are considered sequels to Dragon Ball Z, the power levels of both heroes and villains within Super drastically put GT to shame, including GT’s strongest villain who would be absolutely obliterated if he ever showed his face in Dragon Ball Super.
In the final season of the Dragon Ball GT anime series, a villain known as Omega Shenron comes to the forefront of the Z Fighters’ attention as he attempts to wreak havoc upon the Earth. Omega Shenron, or Syn Shenron, is a Shadow Dragon who is the manifestation of all the negative energy created when one makes a wish. In this instance, Omega Shenron became so powerful after the Namekians wished to bring back everyone that Frieza and his soldiers had killed back in Dragon Ball Z’s "Frieza Saga". Due to the universal impact of wishing almost an entire planet back into existence, the negative energy created from that wish fueled Omega Shenron with power, which he would eventually use to cause chaos on Earth. When he finally came to Earth, however, he was met by the full might of Vegeta and Goku after both were successful in unlocking Super Saiyan 4, and in the end, they were able to defeat him.
While Omega Shenron was the ‘big bad’ of Dragon Ball GT, he wouldn’t last two seconds in Dragon Ball Super. In Dragon Ball Super by Akira Toriyama and Toyotarou, fans are introduced to an all-new, all-powerful character named Beerus, the God of Destruction. Beerus is one of the most powerful gods in existence, even amid other Gods of Destruction as he once was successful in fighting a number of them all at once. Plus, in the anime, Beerus strikes fear into the very heart of the magical dragon Shenron himself when the Z Fighters attempt to wish the Super Saiyan God into existence through Goku. Shenron trembled in fear in Beerus’ presence, which means that the dragon’s antithesis would likely do the same.
If Omega Shenron crosses over into Dragon Ball Super, the amount of raw god-like power he would exhibit and the utter destruction he’d leave in his wake on Earth would undoubtedly raise the attention of Lord Beerus. In the past, Beerus has involved himself in the matters of mortals, with his participation in the destruction of the present-day Zamasu being a prime example. If an entity with god-like powers was causing chaos on Earth—which has become Beerus’ favorite planet because of its exquisite cuisine—then there is a fair chance that he would step in and stop Omega Shenron. Plus, based on Shenron’s reaction to seeing Beerus in Super, it is likely that Omega Shenron would be too scared to fight Beerus at all, and return from whence he came without causing any more problems for fear of his impending obliteration.
While Beerus would assuredly make quick work of Omega Shenron, there would be a chance the God of Destruction wouldn’t actually get involved should the villain cross over from GT. However, that would also be of little concern given the power Goku and Vegeta have been able to unlock. Goku is now able to tap into the angelic power of Ultra Instinct and Vegeta can harness the energy of a destroyer god himself through Ultra Ego. Since the two were able to defeat Omega Shenron in Dragon Ball GT in their Super Saiyan 4 forms, they would assuredly be able to do the same while channeling the power of the gods. Whether from the fear-inducing Lord Beerus or from the now god-like Goku and Vegeta, Dragon Ball GT’s strongest villain, Omega Shenron, would be absolutely obliterated in Dragon Ball Super.