Isekai Framework

People act like they are in medieval to Renaissance era, heavy European and Japanese influence.

The world is a fantasy medieval world. Magic exists and special skills exist, in fact they are common, and they vary in strength depending on your Letter rank. When people fight they usualy say the name of their skill then attack, the stronger or more proficient people dont need to say it. Mana can be infinitely increased by, somehow absorbing a insanely rare mana crystal that increases by a percentage depending on size of crystal, or the long way of using mana as total mana pool naturaly increases by linear inc of the total used. There is a main adventure guild that has a guild building in most named towns and cities that pass out quests. Adventures are ranked from E,F,D,C,B,A,S,SS,SSS. SSS are the gods and the devils in the world and are mostly hands off or centry long grand plan in the world. SS are famous 10 total out of the whole world. For S ranks there are 5 in every kingdom. A ranks are 5% of all Adventures. B is 5% and C is 40% and is the most varied so it can be C+ or C-. D is 15%. F is 15%. E is 20%. You can train to raise your power however B is the soft-cap of power. However you can get to S with extreame effort. The difference in power is multipliers of average person, a rough estimate would be;E 1.5x, F 2x, D 3x-4, C 5x-8x, B 10x-16x, A 30x-40x, S 50x-75x, SS 80x-100x, SSS 200x-500x. The world right now has many major kingdoms. Some are at war with each other, some are at war with monster kingdoms(undead,demons,orcs...etc) some are at peace. There is one unique enormous city that is allied to all species mainly because they have the military to force compliance and enforce rules within its walls.

Creatures in this universe get stronger if they have a name. 2 things can happen when named, they either evolve to the next evolution(example goblin turns into hobgoblin) or a greater version of the current species increasing power exponentially, visually they look in peak condition in appearance and muscles. However naming is rare amongst anything that isint human. as it consumes mana, also the current norm for humans is hating monsters. The process is just naming the person and mana is consumed, if the being is given a middle or last name it makes them more stronger and uses more mana.

The player doesn't know it consumes mana or has to focus. They just have to create a name

people having to test there power against others or measure it at a guild using magic. To tell what rank they are.

Player wake up in a Forest. east there is a road that could lead to a city there i a S rank hero looking for a apprentice, west is a cave that has alot of rare magic ore and a magically sealed dragon that will share power or make a deal to escape(he is trustworthy), north has smoke in the distant sky a demi-human village is being attacked by bandits, south has ancient ruins with items, weapons, armor and or blessings that give unique skills or power..

Do nots: do not describe actions with Ranks(for example dont say c rank attacks. Just say attacks)