A Keystone opens an instanced copy of a dungeon at a tier you choose, with two modifiers drawn for it and a turn budget to clear it in. Clear within the budget and the key comes back a tier higher, cut for another dungeon you have proven at Ultimate; fail and it drops one. You hold one key at a time. Keys come from an Ultimate dungeon boss or a raid final boss when you hold none, and once a week a bountiful key waits at the Keystones board (Character → Keystones): tier = your season best − 2 (at least 1), the week’s rotating modifier, double shards.

Tiers and walls

Tiers 1–4 are the four difficulties as they are (Normal, Hard, Very Hard, Ultimate). From tier 5 every tier is one wall above you: the foes are statted as if they stood 10% further up the rail than your own Power Level, per wall, through the same calculation the Awakened tiers use — so a Lv 1,200 player and a capped player climb the same ladder from their own rung. Loot, EXP and gold stay the difficulty’s own.

A foe’s Rally under the walls heals what it would without them: the walls lift its pool, not its healing.

The turn budget

A browser game counts turns, not minutes. The budget is 40 + 2 per tile of the shortest walk from the entrance to the boss + 8 per foe in the dungeon + 12 per wall; every step and every fight action is one turn (opening a fight is not, and neither is an action the fight refuses — an ability still cooling, an Arte you cannot afford, a press out of turn). The dungeon card shows the turns used against the budget.

Modifiers

Two are drawn for every key. The held key’s modifiers can be re-rolled 3 times in any 24 hours from the Keystones board; the tier and the dungeon stay. Under the Dormant throne the budget grows by 6 turns for every other foe on the floor.

Modifier	What it does
Wardens everywhere	Every third foe is a Warden.
Dormant throne	The boss sleeps until nine in ten of the other foes are down.
No grace	The boss is enraged from its first blow.
Afflicted	Foes open with an affliction on you.
No potions	No potion can be drunk inside.
Walls up	Two walls above the tier.
Silent tongue	Fusions fail.
One life	A death spends the key.

Rewards

A clear within the budget pays 10 Keystone Shards a tier (×2 on a bountiful key), a place on the season ladder and the next key a tier higher. From tier 5 a clear also mails a reward piece with a guaranteed affix (tier III from tier 10) and a Legendary chance of 5% per wall, at most 50%. The boss drops its usual loot either way. Over budget, a death or a walk-out before the boss: the key loses a tier.

The ladder and the vendor

The ladder keeps each class’s best tier for the season (a quarter). When a season closes its top 10 accounts are paid in shards by mail, 500 for first, the way the Labyrinth settles. The vendor on the board sells:

Item	Price
Ascendant Sigil	20 Keystone Shards
Soulbinding Vial	300 Keystone Shards
Re-cut the key (same tier, another dungeon)	50 Keystone Shards