Critical Coin is a rare card you can equip in The Tower: Idle Tower Defense. It adds a coin-drop effect tied to critical kills on basic enemies, making it a modest economy boost for runs where your crit rate is high.
Critical Coin
When you have Critical Coin equipped, any basic enemy killed by a critical shot has a percentage chance to drop coins. The exact chance scales with the card's level, which you can see in the table below.
Note that the effect only triggers on basic enemies, not elites, bosses, or other special types, and the killing hit must be a critical. If your build rarely lands crits, this card will do very little for you.
| Card Level | Effect |
|---|---|
| 1 | 15% |
| 2 | 18% |
| 3 | 21% |
| 4 | 24% |
| 5 | 27% |
| 6 | 30% |
| 7 | 33% |
Card Mastery
Unlocking the Critical Coin mastery costs 1000 stones. Once unlocked, it changes the card's effect so that a successful trigger drops two coins instead of one.
In practical terms, the base card gives a 33% chance to drop one coin on qualifying basic kills; with the mastery, that same 33% chance drops two coins instead. The mastery only works while Critical Coin is in your active loadout, so you still need to spend a card slot on it to benefit.
| Mastery Level | Value |
|---|---|
| 0 | 10% |
| 1 | 20% |
| 2 | 30% |
| 3 | 40% |
| 4 | 50% |
| 5 | 60% |
| 6 | 70% |
| 7 | 80% |
| 8 | 90% |
| 9 | 100% |