Naruto isn't the only manga wherein warriors can obtain highly coveted eyes to achieve god-like powers or that features weaklings who undergo overly ridiculous (and immensely dangerous) training like Ichigo does in Bleach. A character originally damned to a pathetic life in a new ongoing manga experiences all that and more after getting violently massacred by a colossally strong killer bear and a pack of hounds.
Written by Ibara Kino and Fuji Morohoshi, The Unfavorable Job [Appraiser] is Actually the Strongest introduces a world where people are bestowed one job at birth that stays with them for life. Ain has the great misfortune of being an [Appraiser], one of the lowest-ranking jobs in the worst possible category. But he tries to make the best of his unideal situation by utilizing his skills to help adventurers.
Although Ain joins a group, they later betray him, a disgraceful act that leads to Ain getting ripped apart by hounds and his eye torn out by a colossally massive bear before he's saved by the guardian of the sacred tree Yggdrasil. This guardian, compelled by the spirit of Yggdrasil who manifests in the physical realm as a girl, replaces the boy's eye with one blessed by the spirit that augments his power of appraisal. Now he can read the movements of his enemies and steal their powers.
This concept of special eyes granting users unfathomable powers is quite prevalent in Naruto, most notably through the Sharingan, the dōjutsu kekkei genkai of the Uchiha clan that bestows the abilities of Insight and Hypnotism. While proprietary to the Uchiha, the Sharingan can and have been stolen or given to others including the shinobi Kakashi of the Hidden Leaf Village who received one once he'd lost his left eye. Interestingly, one of the Sharingan's abilities allows the shinobi to copy almost any jutsu they see, similar to Ain's.
But despite Ain now having an incredible eye in [Appraiser], he must now partake in special training provided by the guardian so he can go home, once more at the behest of the spirit. Since the guardian must stay in close proximity to Yggdrasil, she can't guide him to safety. And even with his new eye, Ain would not be able to protect himself, so she has no other choice. Angered by her unfortunate predicament, the guardian decides to expedite her ordeal as a trainer while indulging a sick, twisted urge by unleashing her inner masochist. This process involves pushing Ain to the brink of death and reviving him with the healing drops of Yggdrasil, which allows him to achieve incredible power within the span of half a month.
This overly hellish training regimen shares many similarities to what Ichigo suffers in Bleach to help him achieve incredible powers within a short timeframe. Unlike Ain's time restraint, Ichigo's isn't arbitrary, as he must save his friend Rukia from being executed. Turns out, her executioners aren't going to wait around for Ichigo to get stronger so he can rescue her. The training is so brutal that Ichigo inadvertently awakens his inner Hollow, a spirit that manifests as a murderous and sadistic psychopath.
Despite these similarities, [Appraiser] stands on its own from Bleach and Naruto as there are many correlations between the manga and Dungeons & Dragons. Additionally, the abilities that the eye unlocks within Ain are proprietary to him as they essentially improve upon his appraising ability while anyone with a Sharingan can utilize its power in some capacity. For example, Ain is able to detect his opponents' movements because, when he activates appraisal, he sees "text" that normally tells him about specific items. Now, appraising can reveal when his attacker will strike and where.