OKAY. I'm kinda upset because I had a whole thing typed up and I tried to add a photo and it didn't save my progress so now I have to start over but it's getting late so I'm just going to ask this one question instead of the many others that I had already typed out. (short rant over)

(1)  In the Adventurer's Backpack, there is a Class called the Rune Mark, essentially a 'spellcaster' who is an artificer, tinkerer, and craftsman. They specialize in runes which can be thought of as spells imbued in written words and symbols. My question is "is the Fire Rune overpowered?" Maybe I'm looking at it the wrong way, but it seems to me that even a 4th level Rune Mark can deal 64d4 + 256 fire damage over the course of 4 rounds. Or maybe the damage is 1d4 + 4 per round, in which case, why is there an area of effect?

(I got 64d4 fire damage by multiplying the available spaces (16 spaces= 4 spaces x 4 spaces) by the duration of the spell (4 rounds), and I got +256 fire damage from multiplying the available space (16) by the duration (4) and by the additional damage (+4))

Can someone, anyone help me with this? What do you guys think? Here is a link to the picture of the Fire Rune damage, duration, range, and area of effect table.

https://www.pinterest.com/pin/837458493185041296/visual-search/?x=15&y=1...

And here's the ctrl c ctrl v text of the Fire Rune.

FIRE (Int) (Roan ot Plum) CT 1 R see below D instant SV see below SR yes Comp S

This rune allows the rune mark to create fire. The rune affects a single target or a 5’x5’ area of effect +5’ per level of the rune mark. If cast upon combustible material, the fire lasts as long as the material burns. If cast upon non-combustible material such as iron, stone, etc., it lasts one round per level of the rune caster.

Fire ignites combustible items such as torches, wood, grass, clothing, etc. A rune mark can also place fire on non-combustible items such as a sword, control fires that are already burning, extinguish fire, or, when used in conjunction with other runes, create steam, etc. The rune does not create a magical fire; it allows the rune mark to make or manipulate natural fire. If cast upon a torch or fire the flame burns as any normal torch or fire.

If cast upon combustible material such as clothing, the clothing must make a saving throw (CL equal to the rune mark’s level). If cast upon a weapon it deals an extra 1d6 points of damage, double that against cold-based creatures. If inscribed upon a person, that person catches fire. The fire is not magical however, and it will burn whoever it is cast upon, but it does not receive a magical hit bonus or damage. The rune mark can extinguish flames in the area of effect if so desired. Consult the following chart for range, damage to other individuals upon which the rune is cast directly, and area of effect. Always add level to damage. After 12th level, continue to expand range and area of effect, but the damage remains at 8 plus the level.