There are seven custom classes, or paths, available in Arelith.
- Main article: Warlock
The warlock is a subclass of the bard. Warlocks gain magical powers by bargaining with demons, devils, or unseelie fey.
Warlock does not have to be selected at character creation: bards can make a pact later by finding the appropriate NPC.
 Totem Druid
- Main article: Druid#Totem animal
Totem druids gain improved wildshape abilities in exchange for being weaker in their unshifted form. On taking a totem, a character immediately loses 4 STR, 4 DEX, and 4 CON, and gains the abilities of his or her totem.
A totem can be selected by a druid after character creation by finding the appropriate NPC.
- Main article: Ranger#Archer
Archer is a subclass of the ranger. Archers give up their two-weapon fighting feats in exchange for the ability to craft a bundle of arrows each day. The arrows increase in power with archer levels.
The archer path can only be selected at character creation.
- Main article: Ranger#Sniper
Sniper is a subclass of the ranger. Snipers give up their two-weapon fighting feats in exchange for Point Blank Shot and Rapid Shot as bonus feats at level 1 and Mobility as a bonus feat at level 9.
The sniper path can only be selected at character creation.
 Path of the True Flame
- Main article: Sorcerer#Path of the True Flame
A Path of the True Flame sorcerer can cast an unlimited number of spells per day, but is limited to evocation spells. This restriction includes spells cast from items such as scrolls and wands. This means that True Flame sorcerers cannot use healing potions or Raise Dead scrolls.
True Flame sorcerers can use any epic spells, however; both those that come from the Epic Spell line of feats and the epic spells that come from the [[Spell changes#Spell Focuses|Epic Spell Focus]] line of feats in Arelith. They do not, however, get more castings of those spells per day than a normal sorcerer would (i.e. they can only cast Hellball and Greater Ruin once per day).
The Path of the True Flame can only be selected at character creation.
- Main article: Kensai
Kensai is a path selectable by Barbarians, Fighters, Monks and Rogues.
A kensai gains:
- Permanent haste (coupled with a speed reduction effect of -30%)
- They are prevented from equipping any ranged weapons
- Cannot use spells from any source, including feats that replicate the effects of spells.
- +10 discipline.
- Main article: Cleric#Healer
The healer is a subclass of cleric. Healers lose (and cannot regain) all weapon and armor proficiencies except for Simple weapons. In exchange, they gain the ability to cast raise dead 3 times per day and cure serious wounds 5 times per day.
The healer path can only be selected at character creation.
- Main article: Barbarian#Tribesman
The Barbarian is able to get rid of his rage abilities, in exchange of casting a warrior of the barbarian's level and race of whatever the race that the Barbarian is. The barbarian can summon a maximum amount of 2 summons, and can use it as many times as their rage is per day.
Note, that whatever armor(or clothing) you wear your summon will have the exact same armor as you, but will not carry the same weapon as you. Instead they carry 2 Axes. Terrifying rage, and thundering rage have no effect to the summons