Active Skills and MP: Costs and Casting

Active skills are the game’s spells, and the game calls the things that hold them grimoires. You do not learn them, buy them or slot them from a menu. You find an artifact that grants one, carry it in your bag, and add its skill to a quick slot from the artifact’s own tooltip. Drop the artifact and the spell goes with it.

That single fact explains most of the confusion around them: a grimoire is an artifact first. It occupies a bag slot, it belongs to combo categories, it has a level, and everything that happens to an artifact happens to it.

What MP actually pays for

MP is spent on spells and on weapon special attacks, out of the same bar, and it recovers quickly once you are out of combat. You start a run with 50.

That shared bar is the part people miss. Every one of these is drawing on it:

• Grimoire casts. Cost is listed per level on the skill’s own page.
• Weapon special attacks. The great sword’s Whirlwind and the sword and shield’s Cleave cost 15 each, the crossbow’s Power Arrow 10, the blade’s Heavy Slash 5. The dagger’s Parry costs MP too.
• Blocking. On the sword and shield, every hit you catch costs 10 MP, halved when you time it into a perfect guard. A shield player who casts freely will find the shield stops answering.
• Reserved MP. Some effects — summons especially — lock away part of your bar for as long as they are active. That MP is not spent, but you cannot use it either, so your working maximum is smaller than the number on the bar.

Anything that reads as an MP problem is usually a competition problem: two of the four above are fighting for the same pool.

Costs move with the artifact’s level

A grimoire artifact has a level like any other artifact, and the skill it grants is written out level by level — MP cost, damage percentage, base damage, all of it. Raising the artifact moves the spell to the next row.

The direction is not the same for every skill, and this is worth checking before you enchant. Support and buff spells generally get cheaper as their artifact climbs. Heavy damage spells generally get more expensive, because the damage climbs faster than the cost. Neither is obvious from the artifact’s rarity, so open the skill in the active skills database and read the MP row before you spend an enchant or point a tablet at it.

Because tablets change artifact levels, they change your spell costs as a side effect. If you are laying out a bag around a grimoire, the bag planner is where you can see what a tablet does to the slot that grimoire sits in.

Cooldowns and charges — two very different spells

Every skill has a cooldown, and some also carry charges: casts you can spend back to back before the cooldown becomes your limit. The split is stark enough that the two kinds of grimoire play nothing alike.

Bolts are your sustained option. Air Bolt has a one second cooldown, five charges and costs 2 MP; Earth Bolt also comes round in a second and holds nine charges. These are meant to be woven into normal attacking, not saved.

Set-pieces are the opposite: one charge, a long wait. Meteor Shower is on a 26 second cooldown, Thunder Armor 25, Haste 38, and ATK Boost Buff 40. At those intervals a cast is a decision about a whole fight, not a rotation. Casting a 40 second buff on a trash pack means going into the next room without it.

Casts also have a wind-up before they go off, listed on the skill page as its charge time. It is short, but it is long enough to matter when something is already swinging at you — and attack speed affects cast speed, so a fast-attacking build casts faster too.

Making MP go further

Four systems change the economics, and they stack:

• The Academy combo. Two artifacts give Grimoire Haste +12, four cut grimoire MP cost by 15%, and ten give Grimoire Damage +15% along with MP Regeneration +8. This is the dedicated caster combo and the MP cut at four is the cheapest real relief in the game.
• The Lake combo. Three artifacts give Max MP +20 and MP Regeneration +5, six push that to +30 and add damage to MP-consuming abilities, nine to +40. Lake grows the bar; Academy lowers the prices.
• The Wisdom talent. Every level adds MP Regeneration, and level 5 adds MP Steal +5 and Max MP +10 — steal turns your weapon damage back into casts. Check the rows on the talent list before you commit points.
• Costumes. Ghost makes grimoires cost no MP at all in exchange for 40% of your weapon damage. Scholar Lizard fixes Max MP at 80 and stops it decreasing, but sets Max HP to 20. Red-Hooded Rabbit gives Efficiency When Recovering MP +50% for 10 less Max MP. These are the most extreme swings available, and each is a real trade — read them on the costume list.

Where the grimoire sits matters

Position is not cosmetic for casters. Some artifacts reduce the MP cost of the grimoire in the slot to their left; others speed up the cooldown of the one to their right; others only trigger at all when there is a grimoire next to them. Put your expensive spell in a random corner and those effects do nothing.

This is ordinary bag work — the same placement rules that govern tablets and artifact levels — but caster builds feel it more sharply, because a single misplaced slot can be the difference between a spell you can afford twice a fight and one you can afford once.

What fires on its own, and what does not

Your grimoires do not cast themselves. Every skill in a quick slot is a button you press, and if a spell is not going off, nothing is broken — you have not pressed it.

What does run on its own is a separate class of effect:

• Artifacts that cast for you. A few carry a trigger instead of a quick slot: one casts the bolt grimoire sitting in your bottom slot on a repeating timer, another casts a spell after a number of successful blocks. These are the exceptions, and each one says so on its own page in the item database.
• Combo mechanics. Storm Cloud, once its combo is active, summons a cloud that strikes nearby enemies by itself. Solar Blade throws a blade whenever you deal damage with a weapon attack or a grimoire, and the thrown blade lands on the ground where you can pick it up again. Neither needs an input.
• Weapon effects. Some upgrades fold casting into your attacks — and one, Ilonica’s Spirit Staff, takes direct casting away entirely in exchange. If you are building around spells, check what an upgrade does to them before taking it; weapon upgrade routes explains how to read that off a branch map.

The practical version: press your own spells, let the combos run themselves, and watch the one bar that both your spells and your weapon’s defensive move are spending.