Character Points (CP) are used by characters to gain new skills and learn spells. Generally speaking, the more Character Points a skill or spell costs, the more powerful it is. Likewise, the fewer Character Points a skill or spell costs, the less powerful it is.
Character Points are primarily earned by gaining a new Character Level. Each level will give the character a certain number of Character Points, with levels 1-9 giving 10 CPs per level, levels 10-19 giving 20 CPs per level, and levels 20-30 giving 30 CPs per level.
There are alternate means to earn Character Points. Some methods, such as Achievements, require the character to perform certain actions (like reading enough books or eating enough food).
The total number of Character Points available from Character Levels is 620. The total number of CPs available all told has yet to be determined.
It is not necessary to spend Character Points as soon as they are earned. They can be saved, or banked, for a later time, to purchase a more expensive skill, or for any reason the player decides. There is no restriction on the amount of Character Points that can be carried from level to level (except when entering a new Tier, as explained below).
A character must spend a certain amount of Character Points before moving from one Tier to a higher Tier. A character must spend at least 70 Character Points before they can move from Tier 1 to Tier 2. Before a character can move from Tier 2 to Tier 3, they must have spent at least 250 Character Points.
Note that Character Points do not carry over between Breaths. If your character has extra unspent CP at the end of a Breath, that CP will not be available for them to spend at the start of a new Breath. However, if a character has at any point earned Achievement Badges that granted CP in a prior Breath, they will receive that CP again upon reaching a higher Tier in the new Breath.