(Fantastic Force I#12 (fb) - BTS) - When young Franklin Richards was brought to Elsewhen to control his psionic abilities, Koshima was involved in the construction of a psycho-armor specially modified for the boy. The suit, stored in a pocket dimension, came equipped with a built-in limiter that kept the preteen's massive psi powers in check. The limiter could only be deactivated by a release sequence that Koshima committed to memory (see comments).
(Fantastic Force I#10 - BTS) - Hoping that Koshima and the Psi-Masters could help restore his fragmented psyche, Franklin Richards returned to Elsewhen with his etheroid counterparts Avatar, Ego-Spawn and Tattletale in tow.
(Fantastic Force I#11 (fb) - BTS) - Elsewhen had come under attack from the dimension destroying Great Nothingness (caused by Vangaard). The phenomenon had already devoured several parsecs of cross-time reality, forcing Kargul to mobilize Elsewhen's forces.
(Fantastic Force I#11) - Monitoring the situation from Kargul's tower of wisdom, Koshima warned the warlord that sending Elsewhen's troops against the Great Nothingness could lead to incalculable losses. He predicted that the situation had become so dire all of Elsewhen roughly had 37 minutes left to exist. Kargul grew enraged, but the psi-master reminded him that he only spoke the truth. Before they could plan their next step, Franklin and his apparitions burst into the royal chambers, looking for Kargul. The warlord told him his problems had to wait, for the time of culling had come and the arrival of its harbinger was imminent.
(Fantastic Force I#11 - BTS) - Kargul sent his men out to confront the Great Nothingness.
(Fantastic Force I#11) - Koshima, Kargul and Franklin watched in horror as Elsewhen's finest psi-warriors fell prey to the effects of the Great Nothingness, turning them into helpless children before rapidly aging them up until they died of old age. Unsure of their next move, Kargul allowed Franklin Richards to call in the Fantastic Force.
(Fantastic Force I#11 - BTS) - During their interdimensional trip to Elsewhen, courtesy of Huntara's lance, the Fantastic Force was caught in a trans-temporal field caused by the arrival of the harbinger of nothingness: Vangaard.
(Fantastic Force I#12) - Thirty-two
minutes before the end of Elsewhen, Koshima kept silent as he, Kargul
and Franklin watched the confrontation between Vangaard and the
Fantastic Force on the monitors in the tower of wisdom. (Fantastic Force I#12 - BTS) - The Fantastic Force only lasted three minutes against their foe before Huntara teleported them to safety. Arriving on Elsewhen proper, they were perplexed by the disappearance of Devlor.
(Fantastic Force I#12) - With a third of his fleet destroyed and the Fantastic Force unable to stop Vangaard, Kargul decided he had to become personally involved. The warlord ordered Koshima to bring forth the armor of god, a Devastator-class warsuit of immense power that would potentially fry the user's brain. Franklin could not allow Kargul to sacrifice himself and psionically knocked him out before he could take off.
(Fantastic Force I#12 - BTS) -
Franklin used the brief moment of chaos to slip past Koshima's
formidable mental defenses to retrieve the release sequence of his
psi-armor's limiter. (Fantastic Force I#12) - Koshima was left in charge while Franklin and his counterparts flew off to confront Vangaard. Freeing himself from the limiter's effects, Franklin used the full force of his massive psionic potential to temporarily halt Vangaard, leaving his opponent open to a conversation with his Earth-616 counterpart Johnny Storm. He convinced Vangaard to spare the Chosen Realities and leave.
(Fantastic Force I#13 (fb) - BTS) - Franklin Richards only survived the cataclysmic shockwaves generated by his fight with Vangaard by hiding inside his armor's pocket dimension. He was eventually freed and brought to Koshima who set out to cure him. Koshima placed Franklin in the Zero Chamber, an advanced sensory deprivation unit that allowed his mind to restore itself. Koshima also crafted a modified and improved psycho-frame armor for Franklin that he could summon from infra-space using the subcutaneous recall circuit he had implanted in the teen's wrist.
(Fantastic Force I#13) - Koshima attended the celebrations following Vangaard's defeat. He was on hand to explain Devlor's sudden reappearance as an effect of their encounter with Vangaard and happily used his mastery of psioni-technology to repair the Human Torch's costume. Impressed, Storm offered the old sage a job as tailor, but he respectfully declined, claiming his duties as a psi-master were more than sufficient. He then told a relieved Kargul that Franklin's restoration had been a success, retrieving him from the Zero Chamber and reuniting him with his teammates. Koshima witnessed how Huntara decided to stay in Elsewhen, but not before teleporting the other members of the Fantastic Force home.