Goku's Death Makes Dragon Ball's Scariest Villain Even More Powerful
Cyre has proven to be one of the most fearsome villains in Dragon Ball, and when Goku dies trying to stop him, the Saiyan warrior makes Cyre even more powerful.

Immediately after his Dragon Ball debut, Cell proved to be the scariest villain to appear in the franchise so far, even if he wasn't initially the most powerful - yet Goku managed to make the villain even more terrifying after Goku tried to die to stop him .
Cell is a biological robot created by former Red Ribbon Army scientist Dr. Gero. During his artificial pregnancy, Cell was given DNA samples by a tiny robot (also created by Gero) that collected them from Goku and just about everyone Goku had come into contact with in his life, including Vegeta, Piccolo, and even Frieza. When Cyre was finally "born," he had wielded the power of some of the most powerful warriors in the universe—though he was nowhere near his prime. Dr. Gero also created two other Androids, number 17 and number 18, which were intended to serve as additional power sources for the Cell. Once Cell absorbs 17 and 18, he becomes Perfect Cell and is nearly unstoppable - and even then, Cell hasn't finished evolving.
In Akira Toriyama's Dragon Ball Chapter 414, Goku sacrifices his life to prevent the Cell from detonating and taking The whole earth is with him. When Cell concentrates all his power inside his body and starts blowing, Goku uses instant teleportation to teleport himself and Cell to King Kai's world, where Cell explodes and kills Goku, King Kai and Bubbles. Unfortunately, Cell himself survived the explosion, as a piece of his brain wasn't completely destroyed, allowing him to be reborn and return to his perfect form -- plus Goku's extremely powerful ability: instant teleportation.
Goku Gave Cell the Power of Instant Transmission

Instant Transmission is a power that Goku learned on the planet Yardrat. Essentially, as long as Goku can determine someone's power level where he wants, he can travel any distance in the universe in an instant. For example, in Dragon Ball Super, Goku is able to teleport to the world of Lord Beerus in the blink of an eye, while the real Angel Whis takes thirty-five minutes to travel that distance. With Goku's death in this Dragon Ball chapter, Cell is able to absorb this ability - which, as mentioned, exceeds the power of Dragon Ball's divine entity.
Thankfully, Cell was killed by Gohan almost immediately after gaining instant teleportation, but that didn't stop him Use it to create last-minute chaos. After he blew himself up and was reborn, Purcell has been stuck in the world where King Kai used to be, and he really can't return to the earth. However, by instant teleporting, Cell was able to return instantly, and when he did, he killed Trunks, and then nearly destroyed the planet again. So while it was short-lived, Goku's death made Cell - at least one of the most fearsome villains in Dragon Ball - stronger.