8 Bit Tower Defense Unit Rarities: The Five Tiers and How to Recognize Them

Quick answer

The five unit rarity labels in 8 Bit Tower Defense are Rare, Epic, Legendary, Mythic and Secret. Rare is the most common tier and Secret is the rarest. Rarity is displayed on the summon menu's RATES panel, on event banners, and in the Units inventory's rarity filter tabs.

• Rare — 70.74% base summon rate
• Epic — 26% base summon rate
• Legendary — 3% base summon rate
• Mythic — 0.25% base summon rate
• Secret — 0.01% base summon rate

The official game listing describes 8 Bit Tower Defense as "50+ units to collect: Rare, Epic, Legendary, Mythic and Secret," so every unit in your squad belongs to one of five tiers. Those labels matter in practice: they tell you how hard a unit is to pull before you spend gems, they sort your collection into filterable groups, and they flag the tier the game ties to evolution. The percentages above come from the in-game RATES panel — the summon menu always displays the current values, so treat that screen as the live source if an update adjusts them.

The five tiers and their summon rates

The summon menu's RATES panel is the clearest rarity reference in the game, listing all five tiers with their exact chances:

Read as individual chances per summon, about 97% of pulls land in the two most common tiers, roughly 1 in 30 summons reaches Legendary or better, a Mythic is around a 1-in-400 chance, and Secret sits near 1-in-10,000. Those are displayed odds, not guarantees — an early Mythic or a long Secret dry spell are both normal variance.

Recognizing tiers while summoning

Open the SUMMON menu and all five labels appear together on the RATES panel, so you can see exactly which tier a result would belong to before spending gems. Summons themselves cost gems — the SUMMON x10 button was displayed at 500 gems — and each pull delivers units directly to you, with newly discovered units added to your Index. New players are pointed here from the start: the tutorial's step 1 is "Open SUMMON to call some in."

Event banners reuse the same labels but list their own entries. The Hollow Night banner, for example, displayed "HEADLESS HORSEMAN - HOLLOW NIGHT / SECRET (0.02%)" and "GRIM REAPER - HOLLOW NIGHT / MYTHIC (0.5%)" — each exclusive showing both its rarity and a displayed chance. These banner entries are separate from the regular summon pool's rate table, so a banner's 0.02% Secret is not the same listing as the base pool's 0.01%.

If you're planning your pulls, the guide to how to get units covers summoning in more detail.

Recognizing tiers in your collection

The Units inventory screen shows the same five labels as filter tabs: ALL, RARE, EPIC, LEGENDARY, MYTHIC and SECRET. Selecting a tab filters your collected units down to that single tier, which makes it easy to see what you own at each rarity and which tiers you haven't pulled yet. Since summon results flow into your Index and collection, this screen is also where you confirm what a pull actually landed.

Secret: the rarest label

Secret is the rarest tier shown on the base rates screen at 0.01%, and the label also appears outside the regular pool on event exclusives — the Hollow Night banner carried the Headless Horseman as a Secret at 0.02%. In short, wherever you see SECRET in the game, you're looking at top-tier rarity, and the percentage printed beside it tells you which pool that entry belongs to.

Mythic: the evolution tier

Mythic is the tier the official description singles out for growth: "Evolve Mythics into stronger forms." Every unit's detail page has an EVOLVE sub-tab where the game states plainly whether that unit has an evolved form — for example, Chameleon and Quill Porcupine both displayed "No evolution," a useful reminder that not every unit has an evolved form. So before counting on an upgrade, check a unit's EVOLVE sub-tab for its status, and the how to evolve Mythic units guide covers the evolution side in detail.

Where rarity fits in your progress

Rarity tells you how hard a unit is to obtain. Once you know the tiers, the units list, tier list and best team picks help you decide which pulls are worth chasing, and since summons cost gems, the how to get gems guide helps you fund them.