Grandma Voice is a tone that Cyborg mimics his grandma with in the episode "Grandma Voice". However, it is more than a simple voice imitation; Grandma Voice actually has a spirit of her own, shown when she is finally ousted from Cyborg's robotic body.
To prove that Mother Mae-Eye wasn't the bossiest grandma around, Cyborg pressed a button on himself that made him start talking like his grandma used too. He quickly took down the evil old woman with a few swift strikes. After the battle, Starfire remarked that the Grandma Voice was pretty funny.
In the morning, Cyborg startled the Titans, as he had gone full grandma- wearing a wig and pink apron. The voice had now not only taken over his speech but his personality... he, or now even SHE, started to act like the Titans grandma, as in telling them to do homework, not dress immodestly, and not "giving any sass". And sure enough the Titans learned to love her kind ways with the help of a song. However, she soon became just too over-caring, so they came up with a plan to bring Cyborg back.
Grandma arrived in Jump City to find Mother May-Eye and the Titans caught in a pie-making machine (by design)... it was now round two of grandma vs. grandma. The two struck blows at each other, although they were kind of weak, like finger wags and hitting each other with rollers. Eventually, Grandma got knocked hard, and the luminescent blue spirit of Grandma Voice left Cyborg, wishing him goodbye.
Later, after Cyborg won the fight and rescued the others, they played the song Grandma Voice taught them, and outside the Tower, Grandma Voice's ghost could be seen dancing to the tune by her tombstone, too.
- The episode is not clear whether the voice and its spirit are just a part of Cyborg's soul or the ghost of his actual grandma, Maude Stone. The headstone denotes the spirit simply as a voice, not his real grandma (also, the spirit is shown wearing cybernetic plates, which is unique to Cyborg). However, as it's an imitation of a real person (his grandma)... well, there's just some speculation that it could be her.
- Cyborg started talking in his Grandma Voice when he clicked a button on his torso, so it's unknown if the Titans could've just pressed the button again to turn it off.
- There's no explanation on how the Grandma Voice became a living being either, as it was simply turned on by Cyborg.
- One of the Grandma Voice's favorite thing to do is slap sense into people, and literally, too... She quite often breaks the fourth wall.