All 30 Skill Cards & upgrade priority | Scroll Dungeon

1. Unlock rule and cost curve

The Skills tab starts with only the six Common-tier cards available. The remaining twenty-four unlock as you upgrade.

Every third upgrade unlocks one new card.
Opening all thirty therefore takes 72 cumulative upgrades.
Each upgrade costs 40 × 1.24^(total upgrades so far) gold.

Total upgrades	Cost of that upgrade	Cards open
1	40 G	6
3	~62 G	7
10	~286 G	9
20	~2,460 G	12
30	~21,200 G	16
40	~182,000 G	19

Scroll Dungeon skills tab showing card tiers Common, Premium and Rare with per-level values — Skill cards grouped by tier. The number in the corner of each card is its current level; the value below is the total bonus so far.

A growth rate of 1.24 is steep. Cost multiplies about 8.6× every ten upgrades, so late upgrades cost several hours of idle income each.

Early strategy — while upgrades are still cheap (under 20 total), anything you pick is worth it. The point is unlocking cards, so just keep tapping. Real decisions only start once a single upgrade costs thousands of gold, around the 30 mark.

2. Full card list by tier

Values in the middle column are per upgrade level. %p adds directly to a probability; % is a multiplier.

Common tier (open from the start)

Card	Per level	Effect
ATK	+5%	Base attack multiplier
DEF	+5%	Base defense multiplier
Max HP	+4%	More waves survived
Gold Gain	+5%	Applies to all gold income
XP	+5%	Levelling speed
Sell Price	+5%	Gear sale revenue

Premium tier

Card	Per level	Effect
Crit Chance	+3%	Critical hit rate
Drop Rate	+3%p	Chance loot appears
Healing Boost	+5%	Stronger campfire and shrine healing
Idle Boost	+5%	Idle gold per second
Energy Regen	+4%	Shorter refill interval, up to 60%
Kill Rewards	+6 G	Flat gold per field clear

Rare tier

Card	Per level	Effect
Lifesteal	+2%	Recover part of damage dealt
DMG Reduction	+3%	Less incoming damage
Luck	+4%	Higher-rarity drop chance
Boss Slayer	+8%	Damage to bosses — the highest single-card rate in the game
Evasion	+2%	Chance to nullify an attack
Combat Regen	+3%	HP recovered on each field clear

Hero tier

Card	Per level	Effect
Crit DMG	+10%p	Critical damage multiplier
Shard Gain	+10%	Hero shard income
Rarity Up	+3%p	Pushes drop rarity up directly
Gem Finder	+2%p	Chance of gems on clear
Energy Cap	+1	Higher maximum Energy — more playtime per day
Revive Boost	+5%p	Chance to revive on death

Legendary tier

Card	Per level	Effect
Mega ATK	+12%	Strict upgrade over ATK
Mega DEF	+12%	Strict upgrade over DEF
Mega HP	+10%	Strict upgrade over Max HP
Golden Hand	+12%	Strict upgrade over Gold Gain
Deathblow	+20%p	Large crit multiplier boost
Indomitable	+5%	Additional damage reduction

3. Why the Legendary tier dominates

Internally, ATK and Mega ATK are summed inside the same bracket. They aren't separate multiplications — they share one multiplier.

Attack resolves roughly like this:

base attack × (1 + 0.05×ATK + 0.12×Mega ATK + hero bonus)

So one Mega ATK level equals 2.4 ATK levels. Since upgrade cost follows the same cumulative curve no matter which card you pick, once Legendary cards are open there is no reason to keep feeding their basic counterparts.

Line	Basic card	Legendary card	Efficiency
Attack	ATK +5%	Mega ATK +12%	2.4×
Defense	DEF +5%	Mega DEF +12%	2.4×
Health	Max HP +4%	Mega HP +10%	2.5×
Gold	Gold Gain +5%	Golden Hand +12%	2.4×

But still upgrade the basics early — the Legendary tier only opens near 72 cumulative upgrades. Until then the basics are your only option, and those upgrade counts are exactly what unlocks the Legendary tier in the first place.

4. Recommended order by stage

Upgrades 1–20 — anything goes

Costs are low and the goal is unlocking cards. If you want an order, Gold Gain → ATK → XP creates a growth loop: more gold means more upgrades, and more upgrades mean more cards.

Upgrades 20–40 — Boss Slayer and Idle Boost

In this range your runs almost always end at the boss. Boss Slayer (+8%) has the highest rate of any single card, and the boss gates your stage clear reward, so it pays back quickly.

Pair it with Idle Boost (+5%) so offline gold funds your next upgrades. With Energy capped at four runs a day, idle income is your real primary earner.

Upgrades 40+ — switch to Legendary

Once Legendary cards start opening, stop feeding the basics and move to Mega ATK and Golden Hand. From there, take Mega HP → Indomitable if survival is the problem, or Rarity Up → Luck if you want farming throughput.

Playing the long game? Energy Cap

Hero-tier Energy Cap (+1) gives no immediate combat power and is easy to overlook, but going from 4 to 5 maximum Energy is 25% more playtime every day. For anyone logging in daily, nothing compounds harder.