Super Robot Taisen OG Saga: Endless Frontier - Plot

Plot

The game begins with an introduction to the Endless Frontier, explaining a brief history of the world and the crossgates. The game opens up with Haken Browning and Aschen Brödel outside of the Mai Tierra, they enter and explore what remains of the ruins, with debris being cleared away with Haken's Night Fowl, until they come across a large security locked doorway. Haken becomes nostalgic as he remembers that it had been 23 years since he had last been there, after a brief talk with Aschen he orders her to open the door. Unfortunately the password mechanism proves to be too complex for Aschen to hack so she asks Haken to use her "password cracking subprogram". He reluctantly agrees, and it is revealed that it was an overdrive mode that gives her a tremendous power boost, but also creates a personality split from stern and stoic young women to a hyperactive teen. Using her new strength, she literally tears down the door and they proceed onwards.

Upon reaching a deeper part of the ship they found that the defenses of the ship had been activated, battling through the defense droids they come across a second door, this time too powerful to break down. Exploring what they could, they stumble upon a young girl sleeping in a bed in one of the rooms. Upon waking up, she introduces herself as Kaguya Nanbu from Kagura Amahara, their neighbor world. It is found out that she is in fact a princess of the Nanbu Clan with a bounty on her to anyone who brings her back. As bounty hunters; Haken naturally decides to escort Kaguya home for money, and with a key card Kaguya found they proceed through the previously unpassable door. Continuing further they eventually come across two battle droids, far superior to the ones they faced along the way, but manage to destroy them. Unable to proceed through the next door, they return to the Zeit Krokodil and meet the vice-captain Lee, a weretiger, and the half elf mechanic Marion. After the greeting, and being warned to look out for the Phantom (or Black Specter), they leave to collect Kaguya's bounty.

On their way, briefly passing over an unstable Crossgate, they enter the city Trodel Stadt and meet John Moses, Haken's father, where it is revealed they are not related by blood and Haken is ordered to investigate the Mild Keil crystals, otherworldly energy created substance that didn't originate from any of the worlds in the Endless Frontier. Leaving the town, they travel into the Schlafen Celeste, an inactive ship with numerous teleportation pods, which is revealed to be infested with Mild Keil crystals. Continuing on they come across a strange android and pursue her only to encounter three Goblins that were transported into the Schlafen Celeste. Slaying the goblins and losing the android they continue to the crossgate into Kagura Amahara.

Upon arriving, they immediately travel to the capital of Kagura Amahara; Takatori Castle. After stopping at Shirou's, a friend of Haken's, shop they are greeted by Sanuki Nanbu. Although ready to drop Kaguya back Haken and Aschen find that she was missing. Sanuki however is unconcerned and tells them that she is probably at Fujisakura Altar. However Haken notes how suspicious it was that they are paying to bring Kaguya back when she is supposed to be on a pilgrimage journey causing Sanuki to admit that their land were having trouble with Mild Keil crystals, the Phantom and the Shiki-Oni of the east in Megi Castle. Haken and Aschen quickly find Kaguya at the altar, which is apparently Kaguya's mother, and Kaguya promises to introduce them to Suzuka, princess of the Shiki-Oni and a friend of hers from Megi Castle for their services. However she finds out that Megi Castle has become dangerous and becomes determined to see whether Suzuka was alright. Haken, under the guise of hunting the Phantom, decides to escort her along the way and the three of them leave towards Megi Castle.

At Megi Castle they are surprised to find that it was filled with Mild Keil crystals. Fighting their way through rampant Shiki-Oni they find Suzuka and her fiance Shuten arguing in the west hall, from the snatches of conversation it is revealed that it was Shuten that filled the castle with Mild Keil and he was planning to use the crystals to strengthen the Shiki-Oni. Shuten leaves and Suzuka, after some persuasion from Kaguya, reluctantly agrees to lead Haken and Aschen after Shuten through the north gate. However they find their way blocked by Koma, a catgirl bodyguard hired by Shuten to stop anyone from going through the north gate, and two strange creatures with the same energy signatures as the Mild Keil. After defeating them, though Koma manages to escape, they find their way barred by a barricade of Mild Keil crystals. Unable to move further they decide to seek out Otone, Kaguya's master and leader of the Ura Genbu elite ninja's, for more information on the Mild Keil and the Phantom while Suzuka, despite some reservations, joins the team along with her personal mech; The Jyaki-GUN-Oh.

Traveling north, they find Otone at the headquarters of the Ura Genbu on Ryugu Island where it is revealed that they were guarding the Crossgate to Elfetale. They find out that no one had been able to contact Elfetale for some time and all reconnaissance teams haven't returned from the Crossgate, it is also revealed that the Phantom had passed through to Elfetale only two days ago. With their goal clear, Haken and Aschen say their goodbyes to Kaguya and Suzuka and prepare to follow the Phantom. Just as they were about to leave however, Suzuka and Kaguya chase after them, Kaguya to complete her pilgrimage journey and Suzuka to investigate the Mild Keil crystals. With the two princesses in tow, the group moves on to Elfetale. Meanwhile, Otone, after receiving a report on Kaguya and Suzuka, decides to leave them be, but orders a ninja team to track them and keep an eye on them.

Upon arriving, the team immediately travel south to Castle Espina. They are shocked however, to find that it was completely overtaken by Mild Keil crystals. Further investigations find that there was no survivors in the castle. While they were still in the castle the team are startled to find a sudden growth of Mild Keil crystals blocking their path back to Kagura Amahura, leaving them stranded in Elfetale and they immediately realize the crystals were coming from Elfetale. Following the advice of Koma, who followed them, they are forced to travel to Mirabilis Castle in the hopes there may be a crossgate inside they could use.

Entering and avoiding the traps set inside the castle, they quickly across a small girl named Kyon Feulion, a member of the Orchestral army which instigated the Ten year war. After a quick conversation Kyon attacks them in a rage only to be defeated but promptly makes her escape. Continuing further they come across someone named Saya who claims that two members of the Orchestral Army are after her, naturally sparking Haken's interest. Going on they meet a man named Reiji Arisu and a woman simply known as Xiamou who were pursuing Saya. Haken and his team promptly attack and defeat them only for them to find out that they were not members of the Orchestral Army after all and that they too were trying to find a way back to their own world. Banding together, the team travels deeper into the castle only to run into an android Cardia Basirissa who is revealed to have connections to the Mai Tierra and Aschen. After refusing to reveal any information she tries to terminate everyone but is beaten and forced to flee but not before dropping a key card. However, at the end of the castle they find that the crossgate was unstable and unusable and are forced to go back to Espina Castle.

At Espina Castle, the team is made aware that Saya had escaped east and pursue her, believing her path was blocked by debris. However, they find that the debris had been cut open with a powerful beam based weapon and they continue inside. Inside the structure they come across the Serena Pirates who they briefly fight against before continuing on. Just before exiting to southern Elfetale they encounter the Phantom and after a furious fight, escapes them.