Summon calculator
| Rarity | Base | One in | Towers |
|---|---|---|---|
| Common | 36.25% | 3 |    |
| Uncommon | 26.71% | 4 |    |
| Rare | 19.08% | 5 |    |
| Epic | 14.31% | 7 |      |
| Legendary | 3.34% | 30 |        |
| Heroic | 0.267% | 374 |   |
| Void | 0.038% | 2,621 |    |
Click a rarity to work out the summons for it.
Where the odds come from
Each rarity has a weight in the game files, and the chance is its weight over the total. Luck uses the same function the summon screen calls for its odds panel: rarities are lined up rarest first and each one's slice is multiplied by your luck until the total runs out, so the common end gives up the difference. Which tower of a rarity you get is decided by the server, so the towers listed share their rarity's chance.
A Heroic summon gives a hero from the banner you're on. The Standard banner had 1x1x1x1 and Yorick when this was read from the game; the Custom banner lets you pick one hero and only that hero drops. On Standard, getting the same hero in a row tilts the next pick toward the other one. For each tower's stats see the towers table.
Questions
What are the summon odds in Retro Tower Defense?
Common 36.25%, Uncommon 26.71%, Rare 19.08%, Epic 14.31%, Legendary 3.34%, Heroic 0.267%, Void 0.038%. A summon costs 100 Tix.
How does luck work?
Luck Boosts stretch the rare end of the table: the rarest rarities get their share multiplied and the most common ones shrink to make room. At 2x a Heroic goes from 0.267% to 0.534% and Common drops to 0%. Two boosts at once add together (a Luck Boost and a Big Luck Boost make 5x), they don't multiply.
Is there pity?
Yes. You get a Legendary by your 55th summon without one, and a Heroic by your 100th on the Standard banner. On the Custom banner, where you pick the hero, it's 100 summons for a hero you don't have, then 150, 250 and 400 as you own more of its tiers.
How rare is Void?
0.038% a summon, about 1 in 2,621. With a 5x luck stack it's 0.191%.
