
You face a 9-headed hydra. Your sword cuts 5 heads in each swipe (never less), which kills a 5-headed hydra, but a larger one will regrow 2 heads after each swipe. Your scythe cuts exactly 7, but 10 grow back if the hydra lives. Can you kill the hydra? Or better to explore to find more arms first?
Modeled estimate, not a reported figure. How we estimate →
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You are facing a nine-headed hydra. Your flaming longsword cuts five heads in each swipe (no more, no less), which will kill a five-headed hydra, but a larger one will regrow two heads after each swipe. Your storm scythe cuts exactly seven heads, but it makes ten heads grow back if the hydra is not dead. Is it possible to kill the hydra? What if you also had a silver dagger, which cuts just one head, but makes five heads grow back?
Solution: [spoiler]It is impossible without the silver dagger (the number of heads always stays divisible by 3), but possible with the silver dagger, for example: 9 -> longsword -> 6 -> longsword -> 3 -> dagger -> 7 -> scythe -> 0.[/spoiler]
If you liked this puzzle, and you also like dungeon crawling, Hydra Slayer is for you!
The unique combat mechanics of Hydra Slayer are based on the puzzle above. It is challenging both at a short term tactical level (each hydra is a unique challenge, bumping into it with your weapon almost never works), and at a long term strategy level (you have to build a set of weapons which slays hydras effectively). While the early levels could be used to teach arithmetic and tactical planning in a fun way, building an effective set of weapons for late levels is a challenge even for expert number theorists!
Hydra Slayer predates the "roguelike deckbuilder" phenomenon by focusing less on traditional roguelike grid-tactics and more on constructing complex synergies inside a limited inventory of weapons. Not really a deckbuilder, but still fully a roguelike, so this tag is more accurate than usual!
Hydra Slayer currently features a tutorial, 5 player character races with distinct characteristics, 28 enemy types (10 common hydras, each in two varieties, and 8 special enemies), 28 types of equipment including rare artifact weapons with special properties (not counting material and size variations), 15 weapon materials, 18 types of magical items which help you in your quests, three game geometries to choose from, 8 level topologies on very deep levels (including the Möbius strip and Klein bottle), 11 level generators, two endings (a small victory for quick challenges and more casual players, and a big victory for those who want more challenge), and millions of heads to cut!
The Steam version of Hydra Slayer includes online achievements and leaderboards, a "challenge" mode for short but very interesting games (much more unpredictable than the normal play), traps to lead hydras on, and Orbs which provide a powder/potion effect many times at the cost of a weapon slot!
Stats
All-time low is the lowest price we've recorded for this game since we started tracking it.
Languages: English
Engagement
Hours played at review time, across 43 reviews with recorded playtime.
Reviews
Themes across 43 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
positive critical· bar length = how often the theme comes up
Reviews
Good stuff. 6.4/10
What a weirdly brilliant game. As others have said, it's aimed at a very specific audience. You'll probably know if that audience is you, just by reading the store page. I love it. Brilliant.
It's like I wandered into a linear algebra test and didn't study.
Hydra Slayer is one of those games that you end up either loving or hating. That's not a knock against the game in any way; Hydra Slayer is incredible. Zeno Rogue clearly designed for a very specific audience, and Hydra Slayer so good because it is designed for that audience. If, like me, you like traditional roguelikes and you're a math nerd, you will love this game. This game is catnip. It's incredibly addicting, and enormously fun. It's a gigantic math problem that changes and mutates over time, which asks you to plan in both the long and the short term. It's simple on the surface, but the surface-level simplicity belies a frightening amount of complexity. I adore it. The one negative thing I will say is that even for a traditional roguelike, the UI is fairly unwieldy. I'm very comfortable with the genre, so it wasn't that hard to pick up, but it definitely gave me pause at first. If you're reading this, Zeno, thank you so much. Hydra Slayer scratches an itch I didn't know I had, and I can tell that I'm going to be playing it for a long time.
this feels like the kind of game I'd find myself playing at 3:00 AM for absolutely no reason
Like Hyperrogue, this is a very unique roguelike, very tactical, where every situation is an interesting puzzle. While in Hyperrogue the puzzles are more spatially/geometrically oriented, the nature of this one is geared more towards arithmetic. Very fun, and it gets hard quick!
This game is pretty difficult, but it's great fun. If the description "Math-focused pure roguelike" sounds like your jam, get in there. That said, if you aren't big on math, look elsewhere; this game will tax your mathmatical skills.
Such simple math, yet I still can't process it... Good game, though.
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Roguelike matemático hecho por la gente de Hyperrogue. La premisa es que tienes dos armas con una stat de ataque, y el enemigo tiene un numero de cabezas equivalente a sus puntos de salud. Cada punto de salud que pierde, cuenta con una cabeza menos, pero tras cada ataque, el enemigo recupera una parte proporcional del número de cabezas que le has quitado, de modo que tienes que calcular muy bien para eliminarlo dejándolo con el número correcto de cabezas antes del golpe de gracia. Estos devs saben cómo hacer mucho con muy poco. Genios absolutos.
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Trends
Modeled estimate over time, reconstructed from Steam's monthly review histogram.
Momentum
Pace estimated from the game's recent review growth (our daily snapshots) at its own sales-per-review ratio — a momentum signal, not booked sales.
Audience
Estimated from the language of this game's reviews — a proxy for where players are, not official Steam demographics.
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