These are the ones I think are useful to meditate on to understand the subject (ranked by how well I think they get at the archetype) not a comprehensive list.
- Burglar in Goblin Slayer
- Genkai in Yu Yu Hakusho
- Turtle guy in Kurozuka
- Master Splinter
- Master Roshi
- Gran Torino in My Hero Academia
Notable commonalities:
- Ugly, gross, short, often stooped and hairy, sometimes unhygienic but also sometimes meticulously groomed (but still ugly)
- Stated philosophy of egoism, contradicted in practice (being primarily educational). Sounds like Nietzsche, acts more like a samurai or monk in practice.
- Doesn’t mind lecturing on the importance of hard subjects like death, sin, folly, power, and has remarkably well thought-out and clearly expressed ideas about these things.
- Dark humor, cruelty, extreme impatience, unpredictable bordering on demented (and not just seeming demented to the uninitiated, actually being a little demented).
- Most typically used as a mentor character who educates a disaffected young man in the harsh realities of power.
Useful tvtropes:
“Physically, it’s not uncommon for Mentors in Sour Armor to be deceptively short and wiry; others might be Expecting Someone Taller and surprised by the strength and prowess they’ve fit into their small body.”
https://tvtropes.org/pmwiki/pmwiki.php/Main/MentorInSourArmor https://tvtropes.org/pmwiki/pmwiki.php/Main/ZenSurvivor
https://tvtropes.org/pmwiki/pmwiki.php/Main/TricksterMentor
https://tvtropes.org/pmwiki/pmwiki.php/Main/HermitGuru