Kento Fukamiya (Kamen Rider Saber)

Kento Fukamiya (富加宮 賢人, Fukamiya Kento) is a 24-year-old former member of the Sword of Logos who wielded the Raimeiken Ikazuchi and transformed into Kamen Rider Espada (仮面ライダーエスパーダ, Kamen Raidā Esupāda) before he was sealed away by the Ankokuken Kurayami's dark power. Being forced to bear witness to multiple timelines all leading to the world's destruction, he inherited the power of Kurayami, re-emerging from the darkness as the third Kamen Rider Calibur (仮面ライダーカリバー, Kamen Raidā Karibā).

Why He Sucks

 * 1) Initially introduced as a serious character, who was supposed to boost Touma's character development, however he gave little contribution towards growing Touma and even garnering the spotlight in the later episodes.
 * 2) His return as the third calibur, was pretty lack-luster as it was foreshadowed within the initial bits of his post-mortem, and even if the show tried to make it a climatic reveal, it's already established who it was due to those events.
 * 3) During his tenure as the third calibur, he was rendered a mentally-ill sociopath, granted that his personality shift is reasonable, and despite stating his only goal is to seal the Seikens, he would still go far to harm others, as long as it benefits "halting" the destruction of the world, and for Touma's fate.
 * 4) * Not to mention, he WANTED to see Mei's demise as a Megid, without knowing how it could affect one of his comrade.
 * 5) * And even tried to take away Ren's life, just to seal away his seiken.
 * 6) Similar to Touma, His comedic moments are rather forced due to not resonating well into his nature.
 * 7) His "death" was rather uninspiring, and never benefited into making an impactful conclusion to the first-arc, not to mention it was immediately dropped within the transposition of the next-arc, granted it was mentioned a couple of times, it was never re-explored again.