Terra and Ventus first met when the latter was brought to the Land of Departure by Master Xehanort. Terra seemed to be excited to meet him and asked for his name. After Ven provided his name, Terra and Aqua bombarded him with questions which caused him to scream in agony and pass out. Eraqus arrived and revealed that Ven had lost all of his memories. He woke up a few days later and began to train with a keyblade along with Terra and Aqua. At one point, Terra gave his wooden practice keyblade to Ven and performed a mock inheritance ceremony with him. They shared the same dream of becoming a keyblade master one day.
Years later, Terra approached Ven after watching a meteor shower. He and Aqua had their Mark of Mastery exams the next day and Ven promised to come and watch. Terra ended up not passing the exam due to having darkness inside of him and Ven attempted to comfort him. Later, Vanitas gave Ven a warning about the safety of Terra. He attempted to pass this warning onto him but he left the world before he got the chance. Ven left the world immediately after so that he could chase Terra and give him the message.
Ventus and Terra are later reunited in Radiant Garden along with Aqua. They fight a large unversed together and Ven gives him a pass to Disney Town, saying that he was told to give it to his parents. Ventus eventually passed the warning from Vanitas onto Terra. It turns out that he already knew about Vanitas and was not surprised. Terra insisted that he still had more to take care of and told Ven to go home with Aqua. A rift formed between all three of them and Ven was distressed by this.
Much later, Ventus returned to the Land of Departure and asked Eraqus about the X-blade. He decided that it was best to kill Ven in order to prevent this from happening. Around this time, Xehanort informed Terra of what was happening. While Ven was willing to accept his fate and allow Eraqus to destroy him, Terra arrived to save him and pushed him through a portal. He then defeated Eraqus since he wanted to kill his friend.
Ventus and Terra were later reunited in the Keyblade Graveyard along with Aqua. Ventus explained the X-blade to them and told him that he was frightened. Terra and Aqua attempted to comfort him and assured him that they would protect him. Ven asked them to destroy him if it was necessary to prevent the X-blade from being formed. However, Master Xehanort and Vanitas arrived so the trio was forced to battle them. Master Xehanort eventually grabs a hold of Ven. Terra attempts to save him but is knocked away as Ven is frozen. They were later separated.
TerVen is a rather popular Kingdom Hearts ship. A lot of fans feel that it is an obvious parallel to Soriku because Ventus parallels Sora while Terra parallels Riku. The two are best friends and a lot of fans cite the fact that Ven chased after Terra when he left the world and the fact that he has a wooden keyblade from him as a treasured possession. Terra was also willing to kill his father figure Master Eraqus in order to save Ven's life. TerVen most commonly rivals the Terraqua, Venqua and VanVen ships.