Cards are permanent buffs you buy with gems and equip before a run. There are 32 of them across three rarities, each levels from 1 to 7 stars, and how many you can run at once depends on how many slots you have unlocked. This page lists every card value, what each slot and star costs, and the rules that decide which card you pull next.
Updated
- Cards
- 32 12 common · 9 rare · 11 epic
- Gems per pull
- 20 80 copies max a card
- Slots with gems
- 22 58,400 gems total
- Max slots
- 28 with Harmony vault keys
How cards work
Every card pull costs 20 gems. The game rolls the rarity first, then picks a card inside that rarity, so a new copy is always one of the cards you have not maxed yet. Duplicate copies are what level a card up: a card starts at 1 star and tops out at 7 stars.
You only get the effect of cards that are equipped, and you can only equip as many cards as you have slots. That makes slots the real bottleneck early on, which is why most gem guides tell new players to buy slots before chasing card levels.
- Common pull chance
- 80%
- Rare pull chance
- 17%
- Epic pull chance
- 3%
- Rare chance once commons are maxed
- 97%
Card slot costs
The first slot is free and the next 21 are bought with gems, for a total of 58,400 gems to reach 22 slots. Six more slots come from the Harmony tree in The Vault, bringing the cap to 28.
| Slot | Gem cost | Running total |
|---|---|---|
| 1 | Free | 0 |
| 2 | 50 | 50 |
| 3 | 100 | 150 |
| 4 | 200 | 350 |
| 5 | 300 | 650 |
| 6 | 400 | 1,050 |
| 7 | 500 | 1,550 |
| 8 | 600 | 2,150 |
| 9 | 750 | 2,900 |
| 10 | 1,000 | 3,900 |
| 11 | 1,200 | 5,100 |
| 12 | 1,400 | 6,500 |
| 13 | 1,600 | 8,100 |
| 14 | 1,800 | 9,900 |
| 15 | 2,500 | 12,400 |
| 16 | 3,500 | 15,900 |
| 17 | 4,500 | 20,400 |
| 18 | 5,500 | 25,900 |
| 19 | 6,500 | 32,400 |
| 20 | 7,500 | 39,900 |
| 21 | 8,500 | 48,400 |
| 22 | 10,000 | 58,400 |
Slots 23-28 are unlocked with keys in the Harmony vault tree, not gems.
Copies and gems per star level
Maxing one card takes 80 copies, which is 1,600 gems at 20 gems a pull. The card you unlock with counts as the first copy toward 2 stars.
| Star level | Copies for this star | Gems for this star | Total copies | Total gems |
|---|---|---|---|---|
| 1 star (unlock) | 1 | 20 | 1 | 20 |
| 2 stars | 2 more (3 total) | 40 | 3 | 60 |
| 3 stars | 5 | 100 | 8 | 160 |
| 4 stars | 8 | 160 | 16 | 320 |
| 5 stars | 12 | 240 | 28 | 560 |
| 6 stars | 20 | 400 | 48 | 960 |
| 7 stars | 32 | 640 | 80 | 1,600 |
With 32 cards in the tables below, a full 7-star collection is 32 × 1,600 = 51,200 gems, before slots. Once a card is maxed it leaves the pool, and when every available card is maxed the buy button stops working.
Cards locked behind milestones
Five cards cannot drop until you clear a specific milestone. If you max everything else first, the shop will not sell you cards until one of these unlocks.
| Card | Rarity | Unlock milestone |
|---|---|---|
| Recovery Package Chance | Rare | Tier 2, Wave 750 |
| Land Mine Stun | Rare | Tier 7, Wave 250 |
| Nuke | Epic | Tier 11, Wave 10 |
| Ultimate Crit | Epic | Tier 14, Wave 50 |
| Area of Effect | Epic | Tier 20, Wave 80 |
Common cards
The 12 common cards are the flat stat multipliers: damage, health, coins, cash, and defense. Coins and Enemy Balance stay in most farming decks for the whole game.
| Card | Effect ([x] = level value) | Lv 1 | Lv 7 |
|---|---|---|---|
| Damage | Increase tower damage by [x] | 1.50 | 4.00 |
| Attack Speed | Increase tower attack speed by [x] | 1.25 | 2.15 |
| Health | Increase tower health by [x] | 1.50 | 4.00 |
| Health Regen | Increase tower health regen by [x] / sec | 1.40 | 2.60 |
| Range | Increase tower range by [x] | 1.15 | 1.45 |
| Cash | Increase all cash earned by [x] | 1.20 | 2.40 |
| Coins | Increase all coins earned by [x] | 1.15 | 1.45 |
| Slow Aura | All enemies in tower range speed decreased by [x]% | 13% | 31% |
| Critical Chance | Increase critical chance by [x]% | 5% | 11% |
| Enemy Balance | Increase enemies spawned each wave, cash earned per kill increased by [x] | 1.30 | 1.90 |
| Extra Defense | Increase defense percent by [x]% | 5% | 11% |
| Fortress | Increase defense absolute by [x] | 1.30 | 2.20 |
| Card | Lv 1 | Lv 2 | Lv 3 | Lv 4 | Lv 5 | Lv 6 | Lv 7 |
|---|---|---|---|---|---|---|---|
| Damage | 1.50 | 2.00 | 2.40 | 2.80 | 3.20 | 3.60 | 4.00 |
| Attack Speed | 1.25 | 1.40 | 1.55 | 1.70 | 1.85 | 2.00 | 2.15 |
| Health | 1.50 | 2.00 | 2.40 | 2.80 | 3.20 | 3.60 | 4.00 |
| Health Regen | 1.40 | 1.60 | 1.80 | 2.00 | 2.20 | 2.40 | 2.60 |
| Range | 1.15 | 1.20 | 1.25 | 1.30 | 1.35 | 1.40 | 1.45 |
| Cash | 1.20 | 1.40 | 1.60 | 1.80 | 2.00 | 2.20 | 2.40 |
| Coins | 1.15 | 1.20 | 1.25 | 1.30 | 1.35 | 1.40 | 1.45 |
| Slow Aura | 13% | 16% | 19% | 22% | 25% | 28% | 31% |
| Critical Chance | 5% | 6% | 7% | 8% | 9% | 10% | 11% |
| Enemy Balance | 1.30 | 1.40 | 1.50 | 1.60 | 1.70 | 1.80 | 1.90 |
| Extra Defense | 5% | 6% | 7% | 8% | 9% | 10% | 11% |
| Fortress | 1.30 | 1.45 | 1.60 | 1.75 | 1.90 | 2.05 | 2.20 |
Rare cards
The 9 rare cards add mechanics rather than raw stats: Wave Skip, Intro Sprint, Critical Coin, and the Cells card that matters once you are farming elite cells for labs.
| Card | Effect ([x] = level value) | Lv 1 | Lv 7 |
|---|---|---|---|
| Free Upgrades | Increases all free upgrade chances per wave by [x]% | 4% | 10% |
| Extra Orb | A spinning orb with a speed of [x] that destroys enemies on contact (except bosses) | 0.30 | 0.90 |
| Plasma Cannon | Fire one big plasma shot at a boss dropping its health by [x]% | 30% | 54% |
| Critical Coin | If a basic enemy dies from a critical shot it has a chance to drop coins of [x]% | 15% | 33% |
| Wave Skip | Chance to skip a wave and earning coins and cash equal to the previous wave x1.10 of [x]% | 9% | 19% |
| Intro Sprint | Waves Increases by 10 each time, for the first [x] waves or up to your highest wave. A Boss spawns every wave and no coins are earned during Intro Sprint. | 20 | 100 |
| Land Mine Stun | Land mines have a 40% chance to stun enemies for [x] sec (except bosses) | 1.4 | 3.8 |
| Recovery Package Chance | Increase recovery package spawn chance by [x]% | 15% | 33% |
| Cells | Increase Cells earned by [x] (after all multipliers). | +2 | +14 |
| Card | Lv 1 | Lv 2 | Lv 3 | Lv 4 | Lv 5 | Lv 6 | Lv 7 |
|---|---|---|---|---|---|---|---|
| Free Upgrades | 4% | 5% | 6% | 7% | 8% | 9% | 10% |
| Extra Orb | 0.30 | 0.40 | 0.50 | 0.60 | 0.70 | 0.80 | 0.90 |
| Plasma Cannon | 30% | 34% | 38% | 42% | 46% | 50% | 54% |
| Critical Coin | 15% | 18% | 21% | 24% | 27% | 30% | 33% |
| Wave Skip | 9% | 10% | 11% | 13% | 15% | 17% | 19% |
| Intro Sprint | 20 | 30 | 40 | 50 | 60 | 80 | 100 |
| Land Mine Stun | 1.4 | 1.8 | 2.2 | 2.6 | 3.0 | 3.4 | 3.8 |
| Recovery Package Chance | 15% | 18% | 21% | 24% | 27% | 30% | 33% |
| Cells | +2 | +4 | +6 | +8 | +10 | +12 | +14 |
Epic cards
The 11 epic cards are the build-defining ones. Wave Accelerator shortens every wave, Second Wind and Demon Mode are once-per-round saves, and Berserker scales with the damage you absorb.
| Card | Effect ([x] = level value) | Lv 1 | Lv 7 |
|---|---|---|---|
| Death Ray | A powerful ray that destroys enemies on contact (except bosses), with a duration of [x] | 2.3 sec | 4.9 sec |
| Energy Net | Fire a special net at a boss immobilizing it for [x] | 2.5 sec | 4.3 sec |
| Super Tower | The tower becomes super for 15 seconds, tower damage increased by [x] (30 sec cooldown) | 2.5 | 5.0 |
| Second Wind | Revive the tower with half health once per round and creates an invincible shield for [x] sec | 10 sec | 40 sec |
| Demon Mode | Once per Round: Activate Demon Mode. Grants 300x Projectile Damage & Invincibility for [x] sec | 180 sec | 300 sec |
| Energy Shield | Shield that ignores a single attack, replenishes after [x] min | 20 min | 8 min |
| Wave Accelerator | Reduce the cooldown between waves by [x]% | 30% | 54% |
| Berserker | Increase damage by [x] of total damage absorbed this round (max of x8 tower damage) | 0.8% | 1.4% |
| Ultimate Crit | Ultimate weapons gain a [x]% chance to deal critical damage of (Tower Crit Factor) | 1% | 3% |
| Nuke | Destroys [x] of enemies. | 25% | 100% |
| Area of Effect | Increase area of effect damage for Inner Land Mine, Poison Swamp, Smart Missile, Flame Bot, and Land Mine by [x] | 5% | 25% |
| Card | Lv 1 | Lv 2 | Lv 3 | Lv 4 | Lv 5 | Lv 6 | Lv 7 |
|---|---|---|---|---|---|---|---|
| Death Ray | 2.3s | 2.7s | 3.1s | 3.5s | 3.9s | 4.4s | 4.9s |
| Energy Net | 2.5s | 2.8s | 3.1s | 3.4s | 3.7s | 4.0s | 4.3s |
| Super Tower | 2.5 | 2.9 | 3.3 | 3.7 | 4.1 | 4.5 | 5.0 |
| Second Wind | 10s | 15s | 20s | 25s | 30s | 35s | 40s |
| Demon Mode | 180s | 200s | 220s | 240s | 260s | 280s | 300s |
| Energy Shield | 20m | 18m | 16m | 14m | 12m | 10m | 8m |
| Wave Accelerator | 30% | 34% | 38% | 42% | 46% | 50% | 54% |
| Berserker | 0.8% | 0.9% | 1.0% | 1.1% | 1.2% | 1.3% | 1.4% |
| Ultimate Crit | 1% | 1.33% | 1.66% | 2% | 2.33% | 2.66% | 3% |
| Nuke | 25% | 35% | 45% | 55% | 65% | 80% | 100% |
| Area of Effect | 5% | 8% | 11% | 14% | 17% | 20% | 25% |
After all 30 cards available at that point are maxed and you clear Tier 16 Wave 100, each card gains a mastery with its own lab. Those costs and effects are on the Card Mastery reference.
Frequently asked questions
How many gems does it take to max one card in The Tower?
A card needs 80 copies to reach 7 stars. At 20 gems per pull that is 1,600 gems per card.
What are the card rarity drop rates?
Each pull is 80% common, 17% rare, and 3% epic. Maxed cards leave the pool, so once every common is maxed the rare chance becomes 97%.
How many card slots can you have?
You can buy up to 22 slots with gems for a total of 58,400 gems. Harmony vault key upgrades add six more for a maximum of 28.
Why can I not buy more cards?
Five cards are locked behind milestones. If every other card is maxed, the shop stays closed until you reach the next unlock, such as Tier 11 Wave 10 for Nuke.
Can I change cards during a run?
Yes, unless the card shows a lock icon or a boss or fleet enemy is alive. You can also swap between presets that share the same locked cards.
Sources and credits
The numbers on this page come from the community-maintained The Tower - Idle Tower Defense Wiki and were reorganized and rewritten for Towerstats.org. Wiki text is available under CC BY-SA.