Summoning (召喚術 Shoukanjutsu?) is a recurring concept in the Tales series of calling forth powerful, often elemental, beings known as Spirits, notably appearing in the Aselia timeline of games. A person who is capable of summoning Spirits is known as a Summoner (召喚術士 Shoukanjutsushi?).
Tales of Phantasia
Summoning was introduced in Tales of Phantasia as being the art used to call forth Spirits, which even humans are capable of doing by forming pacts with Spirits using jeweled rings. Claus F. Lester is a famous teacher of magic in Euclid who researches summoning alongside his assistant, Milard Rune. When Cress Albane and Mint Adenade venture 100 years in the past of their timeline, Claus's current timeline, they enlist his aid in defeating the Demon King Dhaos. Throughout their journey, the group forms pacts with multiple Spirits, which Claus is able to summon in battle using the pact rings. In one of the game's sequels, Tales of the World: Summoner's Lineage, Claus's descendant, Fulein K. Lester, researches summoning as well and utilizes its power to field monsters and other units in battle. In Tales of Phantasia: Narikiri Dungeon X, Dio has access to a series of costumes capable of summoning as well.
Tales of Destiny (PSX)
In the PlayStation version of Tales of Destiny, summoning is only possible through the use of ancient weapons. It has no impact on the story, existing merely as an option in battle.
Tales of Eternia
Tales of Eternia conceptualizes summoning as the pinnacle of the Craymel Cage system. Normally, the Craymel Cage entraps normal Craymels, the game's substitute for Spirits, to call upon their power through Craymel Artes that only a Craymel Mage can use. Greater Craymels can also enter the Craymel Cage, though only through a device known as a "Parasol", which the Craymel Mages Meredy and Keele Zeibel use to gather the Greater Craymels of the worlds of Inferia and Celestia. Once empowered through the use of artes aligned to their element, Meredy and Keele can incarnate them for powerful effects.
Tales of Destiny 2
In Tales of Destiny 2, Reala and Harold Berselius are able to perform summoning as their mystic arte extension to certain advanced-tier spells. Their version is titled Crystal Incarnation (具現結晶 Gugenkesshou?).
Tales of Symphonia
Tales of Symphonia, which takes place in the distant past of Tales of Phantasia, also employs the concept of summoning in a similar fashion to its predecessor. When the worlds of Sylvarant and Tethe'alla were still combined, around 2,000 years prior to the events of the story, Mithos Yggdrasill formed pacts with Spirits, alongside his companions, to end the Kharlan War. Mithos's pact with Origin enabled him to use the Eternal Sword and rip the planet in two, likewise separating the Spirits. By the events of the story, Sylvarant has lost the art of summoning, and it is somewhat of a rarity in Tethe'alla. Sheena Fujibayashi is a summoner whose failed attempt at forming a pact with the Spirit Volt twelve years prior to the events of the story continues to haunt her, making it difficult for her to being forming pacts with Volt and other Spirits. Despite this, she prevails and manages to form pacts with Spirits from both worlds.
Tales of Graces
In Tales of Graces, Pascal is capable of summoning various Spirits due to her bloodline. Once she comes into contact with a cryas heavily imbued with eleth of a particular element, the Spirit forges a pact with her and allows itself to be summoned. Pascal utilizes summons both as normal spells and as mystic artes.
Tales of Xillia and Tales of Xillia 2
In Tales of Xillia and Tales of Xillia 2, all people capable of using spirit artes channel the power of spirits. Actual summoning is rare and requires a large amount of power; the only examples shown feature the Great Spirits. Spyrite technology can be seen as a perpetual summoning, as it allows a spirit to take physical form for as long as the infused mana lasts.