1. Is it obligatory to belong to a particular clan?
No, unless your character belongs to a canon clan like Uchiha or a CC (custom clan) like Nekura.
2. If you showed me the map with all the countries (lands, kingdoms, empires), cities, towns, villages and other places of importance for the RP would it be completely equivalent with the world in which Naruto (manga) is happening? I need to know the setting and time in order to place my character in this story.
The WSE (warring states era) of the Ninja World does not follow the same timeline as the Naruto manga. In fact, the only thing it has in common with events in Naruto is the appearance of the Sage of Six Paths. The NW currently takes place several hundred years since then. Here’s a Map of the NW and its Lore. I won't get into how the NW works just yet.
3. By default, my rank is the academy student and I am the one who picks 2 basic elements and 1 basic ninja skill to have or is that also arranged by default?
Yes, your rank is academy student and you can choose which elements or skills you want. I’ll go over that soon.
1. You stated that cannon bios can not be customized AS FREELY. Does that implies that they can be customized in some way then? Elaborate and provide examples, please.
Aside from KG, HA, AN, AE, and Modes, the abilities canon and customs bios can have are generally the same. I'm talking about basic fields like Genjutsu, universal abilities you can buy like Fuuinjutsu (Sealing Techniques), or custom fields like CE (Custom Elements) or CFS (Custom Fighting Styles). I plan on explaining these more thoroughly later. Here is a full list of abilities: Link
1. What are bio's core abilities?
Those mentioned in that character's rules thread. Also found in the abilities list.
2. What is AN?
Advanced Ninjutsu. Self-explanatory. Ex. Sound Ninjutsu, Puppetry, Ink Ninjutsu, etc.
3. What are modes?
Something like a temporary boost that gives powerful stat boosts like extra speed or strength. This is about canon modes. Ex. Sage mode, EIG (eight inner gates), CM (Curse Mark).
4. With bio skins you are just changing a cannon character with a custom character while all the abilities of the cannon character remain, correct?
Correct.
1. Can a custom bio have abilities of a cannon bio? Where are the limits here? Say can Todoroki Shouto (BNHA) have Haku´s kekkei genkai?
Yes. Haku's KG is not limited to just him. There are several abilities shown by one character that are available to custom bios but there are also jutsu exclusive to certain characters. For example, Sand Ninjutsu is not limited to just Gaara but his Shield of Sand and Sand Waterfall Funeral are unique to him. Haku's jutsu don't get the same treatment apparently because any Ice user can use his Crystal Ice Mirrors.
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Moving on to what jutsu are available to you at your rank. At
Academy Student rank you have access to C Rank Jutsu,
2 Basic Elements, and
1 Basic Ninja Skill. I'll elaborate. (More information on
You must be registered for see links
)
C Rank Jutsu
-Jutsu ranks from lowest to highest: E < D < C < B < A < S < F
-You have access to
E,
D, and
C rank jutsu you’ve
learned or created.
2 Basic Elements
-Basic Elements: Fire (Katon), Water (Suiton), Earth (Doton), Lightning (Raiton), Wind (Fuuton)
-You can pick
two elements to include in your bio and use jutsu from each element up to the rank your battle rank allows
(C)
1 Basic Ninja Skill
-Basic Ninja Skills: Ninjutsu, Genjutsu, Taijutsu, Kenjutsu
-You can pick
one ninja skill to include in your bio and use jutsu from each element up to the rank your battle rank allows
(C)
-Whether you pick Ninjutsu or not, you always have access to certain E-rank Ninjutsu. I think they are mentioned in the bio template.
Usually you need to be trained in jutsu in order to use them but basic fields like the five elements and ninja skills are learned automatically so you can use jutsu in the fields you've chosen up to C rank
without training in them. I’ll go over training later. You can find jutsu listed in the
You must be registered for see links
section. A Method System thread exists for each of the basic fields that provides explanations on how those jutsu work.