PRESENT TRUNKS SECTION
MISC. SITE SECTION
From a timeline where Androids 17 & 18 dominate and destroy, Mirai Trunks grows up hiding in shadows and skulking about. His mentor is Gohan, the only survivor of the initial battle against the two androids. Gohan, a man now, kept the Androids at bay alone, waiting for the right time to train the young Trunks, who he knew was their only hope. As a young teen, Trunks could not attain super saiyan despite his every effort. It took the death of Gohan to bring that out.
After several unsuccessful attempts at attacking the Androids himself, Trunks finally gives in to his mother's wishes and takes her time machine into the past to bring an antidote to Goku. Perhaps sparing Goku from his death due to a fatal heart disease, Goku could turn the tide on the Androids. Trunks was only 17 when he took the untested machine into the past.
Arriving twenty years in the past, Trunks saves Goku's friends, and the Earth from the vengeful Frieza and his father, King Cold. He then gives the antidote to Goku and tells him of the arrival of the Androids, etc. before returning to his own time.
Three years later, at age 20, Trunks returns again to the past to assist in the slightly altered timeline. His present self in that timeline is a newborn so two Trunks exist simultaneously for a time. Mirai Trunks remains in the past to continue his training and learning from Goku. When the two Androids of the past get absorbed by a more powerful one, Cell, Trunks remains. He trains in the Room of Spirit & Time twice, once with father, Vegeta, once alone. This jumps his age to 22 by the time of the Cell Game. Trunks attains a level beyond super saiyan called ultra saiyan, but it is slow and bulky. It is the level between levels 1 and 2. Trunks is killed in a surprise attack by Perfect Cell during the Cell Game, but is later brought back to life by the Dragonballs.
After the Cell Game, he returns to his own timeline once again. With his newfound powers and skills he easily defeats the two androids and a few years later, nonperfect Cell who can't absorb the now nonexistent androids. He's roughly 25/26 years old when we last see him. Nothing is known about what happens to him or his mother, Bulma afterwards. The city and their house was rebuilt, but nothing more is revealed.
Mirai Trunks also fights with a sword. This sword was bestowed to him by a warrior named Tabion, though it would've been in the present timeline. It is a mystery how future Trunks ended up with it since that incident didn't occur in his timeline.
And unlike Present Trunks, Mirai Trunks is completely alone, having no best friend or sister since neither Goten nor Bra exist in his timeline.
Mirai Trunks is also seen in the Dragon Ball Z movies. He's in movies 7, 8, and 9.