Yuna Shizuma (シズマ ユナ Shizuma Yuna) is a member of GUTS-Select. Being the daughter of Mitsukuni Shizuma, the founder of Sizuma Foundation and one of the founding members of the TPU, Yuna has received a privileged education from a young age. She contributes to the expert team in a myriad of ways in their fight against monster attacks.
Initially unknown to her, Yuna houses the dormant spirit of Yuzare inside her body.
Ultraman Trigger: New Generation Tiga
Yuna was assigned as Kengo Manaka's trainer while he is at GUTS-Select. While visiting the Shizuma residence, Yuna, Kengo and Akito Hijiri were attacked by Ignis, who wanted to kidnap Yuna since she was the heiress to the Sizuma Foundation, but he was driven away for the time being. Hudram appeared and kidnapped Yuna, wanting to get the spirit of Yuzare out of her to tell him where the Eternity Core was located. Yuzare did emerge from her to block a bullet fired her way, and to accelerate the awakening, Hudram summoned Gazort to put her in danger. After the event, Mitsukuni made Akito and Kengo promise not to tell Yuna about it until the time was right. Eventually, she became aware of Yuzare' presence. On her 18th birthday, her father told her about where he came from, as well as giving Yuzare's ring to her.
Kengo, brought back to the present after his time-raveling ordeal, fought against Trigger Dark and the Giants of Darkness. He struggled until Yuzare's spirit came forth from the ring she left behind and through it, Yuna granted Trigger a fragment of the Eternity Core, allowing him to become Glitter Trigger Eternity. However, Yuna was still rather afraid of facing her destiny as the inheritor of Yuzare's role, as she received the memory of Yuzare disappearing after granting the Eternity Core's power to Trigger.
After Trigger's loss to Absolute Diavolo, Ribut decided to train Kengo so that he can learn to control Glitter Trigger Eternity's power, with Yuna taking part as well so that she can learn to face her destiny as Yuzare's descendant. First, Ribut sparred with Kengo, telling him that he was out of focus. He then got the two others to dance in sync with him to get them to empty their minds. When they succeeded, Ribut knocked out Kengo and got Yuna to reawaken him using Yuzare's powers. Kengo realized that while he was the incarnation of Trigger's light, he was also human, and stopped pushing himself so hard, while Yuna learned to get over her fears and face her destiny.
A Kyriel went to the Earth and unleashed the Morpheus R cosmic waves, affecting GUTS-Select and the Giants of Darkness with illusions of their greatest desires. However, Yuna was the only one who was left unaffected. Soon, she was approached by the Kyriel, who deemed that she had the potantial to become a "savior" since she was unaffected by Mopheus R. He explained that only Yuna was qualified because everyone else had sucumbed to to their desires presented to them by the illusions he cast on them. As Trigger fought the three Giants of Darkness, his energy was starting deplete after a long battle. Yuna, with her father's encouragement, faced her fears of using Yuzare's powers and restored Trigger's energy. The Giants of Darkness noticed that Yuzare's power within her had fully awakened before they retreated. Because she had acted in the spur of the moment, the Kyriel also deemed Yuna a failure, before transforming into Kyrieloid. Yuna noticed the "light" within her father and used her power once again to grant him the power to summon Ultraman Tiga, who helped Trigger win the battle.
As a result of her awakening, Yuna's mental fatigue caught up to her, rendering unconscious for three days. In that time, Akito confirmed to the other members of GUTS-Select that she indeed was the descendant of Yuzare. In that time, Barriguiler appeared, summoned to the Earth by Hudram to capture her in exchange for a thousand years' worth of his favourite food. Yuna then woke up and appeared riding on a flying broom made using Guebasser feathers, given to her by Ignis. Barriguiler imprisoned her in his bellybutton prison, but she received Yuzare's memories of her and Barriguiler's battle in ancient times, and used them to convince Barriguiler that Hudram lied to him, saying that Hudram's goal was to reach the Eternity Core and use its powers to plunge the entire universe into a void of darkness. Barriguiler then turned against Hudram, and fought him with Trigger's help. After the battle was over, Barriguiler apologized for what he did and left in a thundercloud, hoping that he and the humans would get along someday.
When Ignis had the Black Sparklence returned to him for the battle against Aboras and Banila, he took the chance to transform into Trigger Dark, and captured Yuna before disappearing. She was brought to the Eternity Core's gateway and was threatened into opening it as Ignis intended to use the Eternity Core's power to revive his extinct race. Yuna simply complied with his demands as she also wanted to believe in the goodness within Ignis. On the way there, they were stopped by Hudram, who cornered Ignis until Akito arrived and helped Yuna get free, allowing Ignis to transform and get his revenge against Hudram. Yuna's faith in Ignis proved not to be displaced as Ignis simply walked away from the Eternity Core after Hudram's defeat.
Yuna was attacked by Carmeara after Darrgon died, and against her will Yuna was forced to open the way to the Eternity Core, allowing Carmeara to access it and transform into Megalothor though at the same time, the Eternity Core became unstable due to the pollution from Carmeara's darkness.Carmeara then attempted to kill Yuna as she no longer required her presence, but failed as GUTS-Select backed her up. Yuna was willing to sacrifice herself to use the Eternity Core's power to defeat Megalothor even at the cost of her own life, but was stopped by Akito before she could do so.
Megalothor soon returned in its secind form and overwhelmed both Trigger and Trigger Dark, though from their past experiences, Kengo and Ignis concluded that a power equal to Megalothor's, that combined both light and darkness, was required to defeat it. While Trigger challeneged Megalothor again as Trigger Truth, Yuna had the task of gathering the Eternity Core's energy into the Nursedessei. Noticing this was happening, Megalothor spread its darkness into the ship, producing copies of both Darrgon and Hudram who were sent to interupt Yuna, but were fended off by her comrades and Ignis. Soon, Yuna finished her mission and allowed the Nursedessei to fire the Eternity Core's energy at Trigger to empower his final attack - True Timer Flash - which destroyed Megalothor.
After the battle, Yuna saw Kengo off to control the Eternity Core's energy, but before he left, the R'lyeh flower which Yuna held started to bloom.
Ultraman Trigger: Episode Z
Two years after Kengo Manaka sacrificed himself to stabilize the Eternity Core, GUTS-Select had been busy dealing with monsters that had been rampaging for yet unknown reasons, until they managed to discover that the Leyrah cult had been causing these incidents by using devices to control monsters. A vision of Kengo, battered and exhausted, appeared to Yuna, alerting her that something bad was about to happen to him. GUTS-Select decided to cooperate on a plan to displace Kengo from the Eternity Core and stabilize it, so that Kengo would not die with the Eternity Core and endanger the world once more.
They agreed to use the energy of the Sun, fired at the Eternity Core by using the Sol satellite that the TPU had built. The Leyrah cultists attached devices they built to the pillars around the Eternity Core's entrance to change the sunlight's energy into a form of light that can be accepted by the Eternity Core, successfully managing to remove Kengo from it. However, in the process, his GUTS Hyper Keys scattered out and went missing. GUTS-Select threw a party for Kengo to celebrate his return.
After Haruki Natsukawa reappeared, GUTS-Select decided to look for the missing Trigger Hyper Keys, fearing that they may have gone under the Leyrah's possession. Kengo regained the Multi Type key form one of the cultists, and then fought Gazort and retrieved the Sky Type Key, while Yuna and Akito tracked the Power Type key to a haunted house, finding it inside a skull prop. They return it back to Trigger and allow him to Type Change, turning the tide of battle with Z's help. However, Z started to rampage because Celebro had possessed Haruki, shooting at GUTS-Select's new captain, Ryuichi Tokioka and defeating Trigger.
Kengo, Akito and Yuna track down the signal of Kengo's stolen GUTS Sparklence and Hyper Keys to the Eternity Core's entrance, finding the Leyrah cultists there being led by Tokioka, who was actually Zabil. He set up a barrier around them, preventing the trio from meddling with him as he gained the power to become Evil Trigger.
As the battle against Evil Trigger raged on, Yuna decided to approach the Eternity Core and splinter a fragment from it like Yuzare did 30 million years ago, despite being aware of the risk. In the process, she sacrificed Yuzare's ring and the gateway tower, but granted Trigger the power to make a comeback, defeating Destrudos, who was summoned by Celebro after Haruki forced him out. Trigger, Trigger Dark and Ultraman Z then finish off Evil Trigger after he had gone mad and grew to giant size.
When the battle was over, Yuna watched as the Eternity Core's gateway tower crumbled, saying goodbye to Yuzare. GUTS-Select then witnessed Zabil dying, regaining his humanity as he disappeared into the light. After Z and Haruki recaptured Celebro and returned to their world, GUTS-Select threw another party for Kengo's return.
- Powers and Weapons
- GUTS Sparklence: A GUTS-Select firearm.
- Kaiju Keys: Devices that store the power of Kaiju.
- Yuzare's Ring: A ring worn by Yuzare. It was passed down her bloodline to Yuna's mother, before her father gave it to her on her eighteenth birthday, strengthening her connection with Yuzare.
- Barrier: Yuzare's spirit uses the ring to project a barrier of light to protect Yuna.
- Energy Charge: Via the ring, Yuna/Yuzare can grant power upon others, to recharge their energy or to unleash their dormant light.
- Astral Projection: Yuna is able to project her astral form to any location, such as the the chamber of Eternity Core; she would also unintentionally sent Kengo's consciousness to Mars via same measure while healing him.
- Eternity Core Power: Yuna can use the ring to control the Eternity Core's power and open the gate to it at a specific altar. However, there is the possibility of her dying if she directly interacts with the Eternity Core's power without another medium to channel it.
Ultraman Trigger: New Generation Tiga
Ultraman Trigger: Episode Z