Videl's First Round
The Elder Kaioshin from Universe 9 was released when King Cold incidentally broke the Z-Sword while fighting Videl, and once freed, Elder Kaioshin offered to unlock Videl's potential (as she was the sword's wielder). Cold opted to transform into his fourth form (the one that Freeza and Coola share), and Videl surrendered the match due to the Elder Kaioshin's awakening power taking too long. With the match over, Videl welcomed the Elder Kaioshin. back to her team's balcony, where he was greeted formally by Kulilin and casually by Yamcha.
When XXI gets announced by the Vargas, Elder Kai is horrified, asking how the Kaios could allow someone like that to come, however, upon seeing him he exclaims that its not him Later, it appears that it is indeed the XXI that horrifies Elder Kai, but he's hiding his true form. After the first night elder Kai tried sneaking into Videl's bedroom, but Videl catched him in the act and hit him.
He has also gone to discuss things with his fellow Kais, who undoubdedly benefit greatly from having their great ancestor around.
After Kakarotto's fight with Pan, prince Vegeta approaches elder Kai to ask for the unlock ability, but Elder Kai immediately insults him and rejects him.
After Kakarotto's defeat by Vegeta in round 3, raitz, under pretence of negotiating for the entire group, goes to elder Kai and offers him an alternative to the empire of the Saiyans, givie him raditz the unlock and raditz will murder Vegeta and nappa and commit their atrocities on a lesser scaile. Negotiatins are still underway.
Like his Universe 18 and 16 counterpart, Elder Kai has the ability to unlock all potential of individuals, or will ever be able to reach. He offered to do this to Videl, stating her power would be greater than final form King Cold. This ritual puts a person at their maximum, they cannot go beyond this point by training. The ritual removes all inconveniences like transformations or Kaioken. The only way to come close, is to naturally train oneself to their absolute maximum, like Gokū and Vegeta have done. But the mystic abilities remains superior.