Region Resonance

The per-region difficulty ladder — frontier kill quotas, gold and crystal fees, the applied-Resonance dial, and the Magic Find / material payoffs.

After clearing the final dungeon — the Throne of Endless Night in the Dark Citadel, where the boss Theron falls — you unlock Region Resonance: a per-region difficulty ladder that you raise by farming, then dial up or down whenever you like.

Resonance is not a run you start. It is a permanent setting on the region itself, and it climbs as a byproduct of normal idle farming.

What Resonance does

Every region carries a Resonance level from 0 to 10, displayed as I–X. Each level adds +10 difficulty rank to every combat tile in that region:

effectiveRank = baseRank + 10 × appliedResonance

So the hard cap is +100 rank over a tile’s base. A tile at base rank 13 fights at rank 23 at Resonance I, rank 63 at Resonance V, and rank 113 at Resonance X. Enemy level follows effective rank, so it can climb past the hero cap of 99 — that is what puts level-100+ Specials on the board.

Resonance applies to combat tiles only. Dungeons and the Endless Delve are untouched by it.

The resistance tax

Rank is not the only thing Resonance changes. While you stand on a resonance-scaled tile, all four elemental resistances drop by 10% per applied level:

fire / ice / lightning / poison −= 10% × appliedResonance

That is −50% at Resonance V and −100% at Resonance X, applied after gear, skills and set bonuses. Your resistance floor is −75% — and negative resistance is not merely “unresisted”: it amplifies the elemental damage you take, so a fire rider against −75% fire resistance lands for 175% of its roll.

Physical damage has no such component; only the four elements are taxed. The same guards as rank scaling apply — the malus only exists on cleared combat tiles of a region with applied Resonance ≥ 1, and never in dungeons, echoed dungeon runs, or the Endless Delve. Dial the region down and the tax goes with it (along with the payout).

Practical consequence: deep Resonance is a resistance check, not just a damage check. Overcapped resistances that looked wasted at Resonance 0 are exactly the headroom that keeps you alive at Resonance VIII+.

Unlocked vs. applied

Each region tracks two numbers:

Value	Range	Meaning
Unlocked	0–10	The highest Resonance you have ever purchased for that region. It never goes down.
Applied	0–unlocked	The level actually in effect right now — a dropdown in the region map view.

Everything keys off applied: effective rank, enemy level, the resistance tax, Magic Find, material drop rate, and Key eligibility. Farming below your unlocked level is the comfortable mode — you still get the full payout for that difficulty, you just make no progress toward the next step.

The dropdown lives in the region map view (top-right of the map) and can only be changed while combat is inactive. If you open the map mid-fight it is read-only until you stop.
Buying a step sets applied to the new unlocked level. Dial it back down immediately if you want.
Uncleared tiles always fight and reward at their base rank, whatever the region’s applied Resonance is.

Raising a region’s Resonance

Going from level L to L+1 takes two things:

Fill the kill counter. You need 1,000 + 250 × L kills in that region, and only kills made at your highest unlocked Resonance count — the frontier. Dying costs the usual penalties but never resets the counter, and progress persists across sessions and accrues offline.
Pay for the step. With the counter full, spend 250,000 × (L+1) gold and 2,500 × (L+1) Echoing Crystals. Both are consumed. Until you pay, the region simply sits at L with a full counter.

Purchasing follows the same rule as the dropdown: region map view, combat stopped.

Step	Frontier kills	Gold	Echoing Crystals
→ I	1,000	250,000	2,500
→ II	1,250	500,000	5,000
→ III	1,500	750,000	7,500
→ IV	1,750	1,000,000	10,000
→ V	2,000	1,250,000	12,500
→ VI	2,250	1,500,000	15,000
→ VII	2,500	1,750,000	17,500
→ VIII	2,750	2,000,000	20,000
→ IX	3,000	2,250,000	22,500
→ X	3,250	2,500,000	25,000
Full climb	21,250	13,750,000	137,500

Taking all five regions to X therefore costs about 106,000 quota kills, 68.75 M gold, and 687,500 Echoing Crystals. The fees deliberately outrun what the quota kills alone bring in, so expect to farm between purchases — and the crystal bill is why the Endless Delve stays useful long after its highscore stops moving.

Payoffs

Magic Find

Resonance-raised combat tiles grant Magic Find once their effective rank passes 100:

magicFind = min(+100%, +1% × (effectiveRank − 100))

That is 0 at or below rank 100 and caps at +100% at rank 200. Because the bonus reads effective rank, later regions are simply better Magic Find farms — the Parched Grasslands top out at +19% even at Resonance X, while the Dark Citadel’s best tile reaches the full +100%.

Dungeons and the Delve get no Resonance Magic Find regardless of their rank.

Material drops

Echo Shard and Echo Core drop chances are multiplied by the region’s applied level:

materialDropMultiplier = 1 + min(+200%, +20% × applied)

So Resonance V triples the shard/core rate (+100%) and Resonance X caps it at +200% — the main reason to push a region you intend to farm for crafting materials.

Keys

A region with applied Resonance ≥ 1 puts its Specials on the Key table. See Echo Ascension for the full boss chain.

The region ladder

Regions start at different base ranks, so they hit the interesting thresholds at different Resonance levels:

Region	Base ranks	At Resonance X	Keys from
Parched Grasslands	1–19	101–119	VIII
Cursed Swamp	20–39	120–139	VI
Scorched Foothills	41–59	141–159	IV
Shattered Mountains	61–80	161–180	II
Dark Citadel	82–100	182–200	— (no Key)

“Keys from” is the first Resonance level at which a region’s top tiles spawn Specials at level 100 or higher — a Special sits +2 levels above its tile. Keys therefore come online hardest-region-first: the Shattered Mountains start paying at Resonance II, the Parched Grasslands not until VIII.

The Dark Citadel is the finale region and drops no Key. Its top tile at Resonance X sits at rank 200 — the designed endgame wall, and the point where Resonance Magic Find maxes out.