You have a pool of points that represents your durability called hit points ("HP"). Your maximum hit points is equal to your level multiplied by your Constitution modifier. Your class, as well as other features, increase your maximum hit points. When you take damage or receive healing, you add to or remove from your current hit points. Healing kits, potions, spells, and other features can heal your hit points. Any hit point healed above your maximum is lost. Once you reach 0 hit points, you start dying. Whenever you finish a rest, you regain a number of hit points equal to your Constitution modifier (minimum of 1).
If you have resistance to a damage type, damage of that type is halved against you. If you have vulnerability to a damage type, damage of that type is doubled against you. Immunity to a damage type causes you to take no damage of that type. Resistance, immunity, and vulnerability are applied after all other modifiers to damage, and multiple instances of resistance, immunity, and vulnerability that affect the same damage type count as only one instance of damage, with immunity superseding resistance, and resistance superseding vulnerability.
A feature can grant you ward points ("WP"), which is a new pool of points that supersedes your hit points when taking damage, regardless if your current hit points is below or at your maximum hit points, and whether you are unconscious or not. If you already have ward points when you gain them from a different feature, you choose which pool of ward points takes effect, possibly replacing the previous one. Unless specified, any ward points lasts until depleted. Features that grant healing can't restore ward points.
You have a pool of points that represents your power over magic and spells called mana points ("MP"), which is composed of your current mana points and your maximum mana points. Your class, as well as other features, increase your maximum mana points. You expend mana points as you use spells and other certain features. You must take the Meditate action to regain any expended mana point.
You have a pool of points that represents your bodily and physical exertion called stamina points ("SP"), which is composed of your current stamina points and your maximum stamina points. Your class, as well as other features, increase your maximum stamina points. You expend stamina points as you use maneuvers and other certain features. You must take the Rest action to regain any expended stamina point.
You have a pool of points that represents your perseverance and mettle called grit points ("GP"). You gain a grit point whenever you fail a d20 roll. Thereafter, whenever you make a d20 roll, you can expend any number of grit points and add them to the roll. There is no maximum number of grit points you can have at the same time, but all grit points are lost when you take the Meditate or Rest action.
A heroic point is a special resource that only the GM can grant. Once you have a heroic point, you can expend it to reroll a d20 roll that you or another player of your choice made. You can only have one heroic point at a time, which lasts until you expend it.
You have a special resource that represents your will to command over companions called spirit, which is equal to your Strength, Dexterity, Constitution, Intelligence, Wisdom, and Charisma modifiers added together. Some features can also increase your spirit. Whenever you have one or more companions following you, subtract their levels from your spirit. Your spirit can't go lower than 0, and you regain spirit when a companion stops following you. A companion that follows one of your companions but obeys you costs you 0 spirit.
Some features require you to attune yourself to them before they can be used. To become attuned to a feature, you take the Attune action within reach of the target of the attunement for the duration. Attuning to a feature consumes an attunement slot, of which you have a number of equal to your aptitude bonus. Any attempt to attune to a feature past this maximum fails. Once attuned, you can then use the feature. An attunement ends if lose any prerequisite for the attunement, you willingly end it, you die, or, in case of artifacts, another creature attunes to it. Ending an attunement restores the attunement slot.