Art Points, abbreviated as AP, are the points required in order for players to perform a Hero Art.
AP is acquired by playing Unit or Action cards. 1 AP is earned for each MP a player spends to play a card.
In the case of Surge of Demonic Power (TDA 075) being used, the new halved MP cost will override the original MP cost. As such, players will obtain AP based on the new MP cost of any cards affected.
When enough AP is acquired, players can then use a Hero Art. Both players can see when their/their opponent's Hero Art is ready as well as its cooldown of 15 seconds after being used.
The AP requirement for each Hero Art can differ, however, the only way the AP of a Hero Art is changed is via a patch.
Some cards will also give AP to players because of their Art Charge ability, in this case, the MP cost plus the Art Charge will give a separate quantity of AP to a player. For example, if Headshot (COR 030) is used, the player will get 3 AP (MP cost) + 2 AP (from the Art Charge), so 5 AP in total. As of The Tale of Amatsu no Kuni expansion, Unit Cards can also have the Art Charge ability.
In terms of the Active Response mechanic, it's important to understand that the AP from the Art Charge will only be given after the Active Response ends, but the AP obtained by playing the Action Cards will be given immediately upon playing the Action Card.
Let's use the Headshot (COR 030) Action Card again as an example:
- A Jill uses Headshot (COR 030), which triggers the Active Response. (Jill obtains only 3 AP at this point for playing this card)
- The Morrigan opponent negates the card by using Unforeseen Interference (COR 117). (Morrigan obtains 3 AP at this point for playing this card)
- Jill chooses to "Resolve" and end the Active Response.
- Count 2: The effect of Unforeseen Interference (COR 117) is calculated.
- Count 1: Due to the effect of Unforeseen Interference (COR 117), Headshot (COR 030) is negated. Jill does not get 2 AP at this point.