
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?
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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
Match the number of heads on the hydra with your weapons to kill them. Quite interesting and difficult at the same time. I recommend this roguelike for someone looking for a small amount of puzzle solving in their roguelikes.
Nice time killer. Though I need a calculator when doing later levels.
Just a plain great game. Simple in it's mechanics and you dont have to be particularly good at math to do quite well!
weird, but very interesting, highly recommend!
I enjoyed this game quite a bit. It's very numbers based, and I'm very numbers stupid, but I managed to persevere. Still need to play it more, but it is an inventive concept and well worth trying.
A very interesting game concept, and it works better than you'd think! The balance is a bit skewed in favor of one or two of the character classes but all are viable.
I wish other games had weapons like this one does.
It was surprisingly good! This math-based roguelike is pretty tense. You're rarely sure of how well a fight will go, and vanquishing a big hydra feels truly epic. Like Hyperrogue, Hydra Slayer is very well balanced and the weapons and consumables you encounter open interesting possibilities. Like Hyperrogue, the downside is a lack of streamlining in the effect of consumables: you often have to read a page of text, then make calculations to foresee what a consumable will do. Sometimes, crucial information is not mentioned, and you'll have to try it out to find out. All in all. Hydra Slayer is a hidden gem full of epic moments.
Grab your sword, your shield and your calculator for this roguelike where every encounter is different! Hydras, the mythical many-headed beasts, come in 10 elementary and some special variants and so does the arsenal of weapons that our hydra-slaying hero encounters during his descent into the depths. Elements affect one another differently, a weapon forged in one of the elements will have a varying impact depending on what kind of hydra you face. Striking a hydra with weapons made of favorable elements for the monster might even be beneficial for it, that is, causing excessive growth of additional heads. But that is not necessarily a bad thing. https://steamcommunity.com/sharedfiles/filedetails/?id=2978703917 Each encounter is a mathematical puzzle: how to beat the hydra with weapons currently at your disposal. You can only strike a hydra with a weapon if conditions for its use are met, which commonly means that the amount of damage the weapon does must be equal or lesser to the number of remaining heads. Or, in the case of specialized weapons, if the number of heads is divisible with it, rootable with it, and so on. For better understanding of how combat works I recommend skimming through the comprehensive guide written by Ibid and before you know it you will be decimating, quasisecting and whatnot those heads to oblivion: https://steamcommunity.com/sharedfiles/filedetails/?id=891556800 Approaches to combat vary considerably depending on what race (out of 6) you choose for your hero. As you delve deeper in their lair the hydras grow bigger and tend to specialize more. Drinking the blood of slain hydras reinvigorates our hero and causes him to grow a little (both replenishing and increasing HP), which is the key mechanic of the game making the combat strategic. In the long run, you have to dispose of individual hydras effectively enough to weigh the benefits from their blood over the damage their heads deal when you engage them. If mathematical theme has you on the fence, I recommend trying it for originality. Which is what I did, and it grew on me. https://steamcommunity.com/sharedfiles/filedetails/?id=2366065757
Such simple math, yet I still can't process it... Good game, though.
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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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