Osty
PetHealth
1 HPAlways 1.
Gold
0 goldThis fight pays no gold.

1/1OstyTurn 1
How to beat Osty
Summoning Osty
Summon X: brings Osty out with X Max HP and X HP.
Already alive: the same keyword raises his Max HP by X instead.
Already dead: it revives him at X.
Bound Phylactery: summons 1 at the start of every turn.
Damage redirection
Die for You: any unblocked attack damage aimed at the Necrobinder goes to Osty's HP instead, after your own Block has soaked what it can.- Non-attack damage such as Burn still hits you.
Using him
He is both a shield and your damage: keep his HP topped up with repeated Summons.- Spend him with cards like Bone Shards or Sacrifice when that is worth more than keeping him.
Notes
- When Osty dies he stays on the field with a hidden health bar until the next Summon, which is why re-summoning is cheap.
- Powers cannot be applied to him while dead.
- Enemy multi-hit attacks are dangerous for him, since every unblocked hit is redirected.
- He is listed among monsters because the game builds him from the same creature model.
From the code
Osty is the Necrobinder's companion, not an enemy: Bound Phylactery summons him at the start of your turn, he has no move of his own and only attacks when one of your cards tells him to.
Changes by version
- Buffed Sacrifice card: Block gain increased from double to triple Osty's Max HP
- Fixed awkward delay when Osty and Kaiser Krab would spawn at start of combat
- Buffed The Boot relic: damage increase now also applies to Osty's attacksBug fixv0.107.1Fixed a crash when Osty dies during a scene transition
All 70 patch notes67 older
- Buffed The Boot relic: damage increase now also applies to Osty's attacks
- Fixed crash when Osty dies during scene transition
- Updated art for Osty in character select screen
- Foul Potion description now specifies that it deals damage to "ALL players and enemies" instead of "EVERYONE", making it clearer that it does not hit Osty
- Foul potion no longer damages Osty
- Fixed an issue where Melancholy card's cost reduction would persist between combats if the reduction was due to Osty dying
- Osty now uses the player's block when he is dealt damage directly (for example, when using an Osty attack on an enemy with Thorns)TextReaper FormLethalityInternal playtestReaper Form and Lethality card wording changed to imply Osty attacks also benefitBug fixPhylactery UnboundInternal playtestFixed a visual issue with Phylactery Unbound relic where Osty wouldn't appear until after you'd drawn your opening hand
- High Five card is now clearer that Vulnerable is not applied if Osty is dead
- Added Osty Summon SFX
- Osty, Byrdpip, and other pets now properly turn around when you attack the enemy behind you in a Surrounded encounter
- Upgrade no longer based on Osty's max HP; stays based on Osty's current HPBug fixThe NecrobinderSic 'EmInternal playtestNecrobinder's Sic 'Em card no longer Summons for other players when their Osty hits the target in multiplayer
- Buffed Calcify card: Osty's bonus damage increased from 3(4) to 5(7)Bug fixInternal playtestFixed Sic'Em crashing when played without OstyBug fixInternal playtestFixed hitching when Osty revives
- Sic'Em Power triggers Summon when Osty hits the target
- While common sense dictates that you can't high-five a dead Osty, we've nevertheless updated High Five card's wording to specify that it can only be played if Osty is alive
- Invoke card now glows gold if Osty has attacked this turnBug fixFossil StalkerInfested PrismSuckStrengthInternal playtestFossil Stalker and Infested Prism monsters' Suck power no longer double-dips on Strength gain when a hit kills Osty and "tramples" over to also hit the player
- Mystic Lighter relic now properly increases the damage of Osty attack cards
- Buffer power no longer prevents Osty from losing HPBug fixTungsten RodInternal playtestTungsten Rod relic no longer prevents Osty from losing HP
- The Formula potion now properly applies to Osty attack cards
- Buffed Empower card: now also says "Osty no longer loses Buffs on Death"Bug fixInternal playtestOsty attacks no longer glow red when combat endsBug fixInternal playtestSingle-target Osty attack cards no longer hit all enemiesBug fixInternal playtestHeart Piece relic now properly excludes damage dealt to Osty from its 20-damage-per-turn threshold
- Changed Make Use card: Osty now attacks and deals the damage instead of Necrobinder
- Rattle card now properly glows red if Osty is dead
- When Necro dies to Doom, Osty dies as wellBug fixHand DrillInternal playtestHand Drill relic is now properly triggered when Osty breaks an enemy's blockBug fixInternal playtestOsty now actually shakes when you play an Osty attack while it's deadBug fixInternal playtestOsty is no longer summoned by dead players' Bound Phylacteries
- Osty's attack cards now glow red if Osty is dead
- Osty now shakes if you try to play an Osty attack while he's dead
- Invoke card now glows gold if Osty is deadInterfaceInternal playtestAdjusted intent position, hitbox size, and center for Osty
- Fossil Stalker now properly gains Strength when dealing unblocked attack damage to Osty
- Health bars no longer show orange when the HP bar size changes (ex. at the start of a multiplayer session, when Osty changes size, when the Thieving Hopper starts flying)Bug fixInternal playtestTide's Binding relic no longer prevents Osty from healing (or other players in multiplayer)
- Randomized Necrobinder & Osty's fire a small amount at the rest siteBug fixThe NecrobinderInternal playtestOsty is now placed correctly at the rest site when Necrobinder is on the far side of the log (no more sitting on Osty)
- Damage numbers on Osty no longer show overkill damage
- Osty no longer layers over byrdpip in game over screen
- Corpse Slug's Ravenous no longer procs when Osty dies
- Osty now grows in size as he gains more max HPBug fixShared FateInternal playtestFixed an issue where playing Shared Fate card would cause a softlock if Osty was dead
- Changed Sentry Mode card: the damage that Osty deals via this card now counts as attack damage, meaning effects like Strength and Vigor now apply to itInterfaceThe NecrobinderInternal playtestOsty's healthbar now shows the blue block outline when Necrobinder has blockInterfaceInternal playtestRemote players' Osty is no longer hoverableBug fixSoul NexusInternal playtestFixed an issue where Soul Nexus's Soul Wither power would decrement when one of its attacks damaged Osty but not the player
- Changed Lethality card: now applies to Osty's attacks in addition to yours
- Remote player's Osty's healthbar no longer reappears when it revives
- Fixed an issue with Unending Service card enchanted with Momentum while Osty is dead not previewing Momentum's extra damage
- Fixed an issue where the Slippery power was preventing damage from Osty's Friendship attack in addition to the attack card that triggered it
- Empower card now shows targeting reticle over Osty
- Osty's body now remains in combat after dying, and plays a revive animation when re-summonedBug fixThe NecrobinderStrengthInternal playtestDamage amounts on Osty attack cards no longer reflect Necrobinder's Strength when Osty is dead
- Buffed Transfuse card: Osty healed HP increased from 10(15) to 15(20)ArtInternal playtestAnimated rest site Osty to be a left hand
- "Summon 5(7). Osty deals 5(7) damage."MentionInternal playtestReworked Milk potion: "Heal Osty for 25 HP."DamageInternal playtest"Osty deals 5 damage twice (3 times)."ChangeSentry ModeStrengthVigorInternal playtestChanged Sentry Mode card: Osty's attacks no longer benefit from Strength or VigorArtInternal playtestOsty now pokes the enemy instead of slamming them for some cardsBug fixThe NecrobinderInternal playtestNecrobinder no longer plays death animation twice if she is killed at the same time as OstyBug fixThe NecrobinderInternal playtestNecrobinder now plays SFX and VFX when Block is hit, even if Osty is outBug fixThe NecrobinderThe InsatiableInternal playtestOsty and Necrobinder are now both properly pulled towards The Insatiable
- Damage from Bone Shards card is now properly dealt by Osty instead of the playerBug fixThe NecrobinderInternal playtestDamage VFX no longer plays on Necrobinder when Osty absorbs all damage from an attackBug fixInternal playtestFixed an issue with the Plague Carrier card where its effect was wearing off if Osty died and was resummonedBug fixInternal playtestOsty no longer gains extra HP in Burly monster roomsBug fixInternal playtestOsty's health no longer occasionally shows up in the top bar HP counter when playing as the NecrobinderBug fixInternal playtestSharp enchantment now displays its damage bonus on Osty attack cards even when Osty is dead
- Added to the gameRemovedInternal playtestDeprecated Osty's Devotion relicChangeStrengthVigorSentry ModeInternal playtestOsty's Strength/Vigor now applies to his Sentry Mode attacksChangeSentry ModeInternal playtestSentry Mode power is now applied to the player, meaning it can be played while Osty is dead and it will still trigger after he's summoned
- Chain Mail Pants card now applies Plating to Osty, not NecrobinderBug fixSlippery BridgeInternal playtestOsty now loses HP first at Slippery Bridge event
- Regen is no longer proc'd on Osty if he is deadBug fixInternal playtestTargeting reticle is no longer shown when targeting an attack on OstyBug fixHexSpectral KnightInternal playtestFixed softlock when Hex is applied to Osty by Spectral Knight
- Lightning orbs no longer hit Necrobinder if Osty is alive
- Reworked Fearmonger card: "Whenever YOU attack an enemy with Doom, Osty gains 6(9) Block."DamageInternal playtest"Osty deals 30(40) damage to ALL enemies."
- Toothed enchantment now properly targets Osty instead of Necro
- Run history now reflects damage taken by OstyBug fixInternal playtestBedlam Beacon event now uses Osty max HP for its HP loss thresholdBug fixInternal playtestBird Faced Urn relic now heals Osty instead of NecroBug fixInternal playtestBlock gained from Despair now prioritizes OstyBug fixSoulThe NecrobinderInternal playtestSoul Buddy relic now applies health gain to Osty instead of NecrobinderBug fixVulnerableInternal playtestVulnerable on Osty is now reflected in then enemy intent damage previewBug fixVulnerableWeakInternal playtestVulnerable/Weak no longer ticks down on the first turn it's applied to Osty
- Necrobinder now starts with two relics: Osty's Devotion and Bound PhylacteryRelated relicBound PhylacteryInternal playtestBound Phylactery: "At the end of combat, heal ALL HP. If Osty is dead, revive him with 1 HP."BlockInternal playtestOsty's Devotion: now "All enemy Attacks and Debuffs target Osty. All Block is gained by Osty."ChangeThe NecrobinderInternal playtestNecrobinder can no longer swap places with OstyMentionInternal playtest"Lose 2 HP. Whenever Osty attacks, he hits an additional time."DamageInternal playtestOsty deals 10(15) damage to ALL enemiesMentionInternal playtest"Lose 1 HP. Osty deals 1(2) damage 5 times."ChangeInternal playtest"Osty deals 5 damage twice. Gain 5(10) Block."MentionInternal playtest"The first time you and Osty attack the same enemy each turn, gain 3 energy."ChangeInternal playtestOsty's max HP increased from 45 to 55DamagePull AggroInternal playtestChanged Pull Aggro: now "Osty deals 5 damage twice(three times)."MentionInternal playtestReworked Heel: "Gain 5(6) Block. Gain 5(6) additional Block for every time Osty attacked this turn."ReworkVulnerableInternal playtestReworked Tackle: now "Osty deals 5 damage and applies 2(3) Vulnerable."InterfaceInternal playtestOsty's health now appears in the top bar when playing as the NecrobinderBug fixInternal playtestMultihit on killing Osty no longer breaks his animationsBug fixBound PhylacteryInternal playtestBound Phylactery now heals Osty to 1 HP if he is dead
- Pen nib now correctly doubles Osty's damage
- The Sentry Mode power no longer triggers when Osty dies
- Reanimate now costs 3 and no longer heals Osty to full on upgradeBug fixVulnerableInternal playtestEnemy intent damage now reflects Vulnerable on Osty if he is in frontBug fixInternal playtestThe text in Osty-attack cards now properly reflects Osty's damage-modifying powers, and the text in block cards now properly reflects the block-modifying powers of whichever creature is in frontBug fixInternal playtestOsty now correctly stays dead on save and reloadBug fixInternal playtestFixed softlock if the Necrobinder dies before OstyBug fixInternal playtestFixed Osty switch button not showing up when Osty revivesTextInternal playtestThe description for the Osty's Devotion relic has been updated for greater clarity
- You and Osty each gain 5(8) ShieldBlockInternal playtest"Osty gains 15(20) Block." to "Osty gains 8(11) Shield."DamageInternal playtest"Osty attacks 5 times." to "Osty deals 5(6) damage 5 times."ChangeInternal playtestIncreased Osty's HP from 15 to 45ChangeInternal playtestEnemy debuffs are now redirected to Osty if he's in frontChangeInternal playtestOsty no longer revives and heals at the start of every room. Instead, Osty can be revived and healed by resting at rest sitesBug fixInternal playtestFearmonger power now triggers when "Osty deals damage" attacks are playedInterfaceThe NecrobinderInternal playtestAdded button for swapping between Necrobinder and Osty being "in front"Related cardSentry ModeInternal playtestSentry Mode: "At end of turn, Osty attacks a random enemy for 10 damage." to "At the end of your turn, Osty deals 10 damage to a random enemy."TextInternal playtestUpdated Osty's Devotion relic description
- Osty's corpse now wiggles if you try to perform an action on him while he is dead
- Make attacks redirected to Osty show VFX on Osty instead of NecrobinderBug fixInternal playtestOsty blocks admage taken in event rooms
- Osty no longer has intents or takes turns and redirects all damage to itselfBug fixInternal playtestOsty not visible ressurecting at the end of combat
- Osty and Necrobinder HP dramatically reduced
- Osty no longer loses powers when dyingInterfaceInternal playtestShow power hovertips while Osty is dead
- We're looking into changing up Necrobinder but not quite yet. However, Osty now attacks the closest enemy so that's a big shiftChangeInternal playtestOsty now attacks the nearest enemy
- New Osty animationsArtInternal playtestUpdate Osty mix settingBug fixInternal playtestDragged Prey card was still dealing damage when Osty was deadBug fixInternal playtestOsty is no longer in the shop rooms. No pets allowedBug fixInternal playtestOsty was attacking dead Decemillipede segments
- Osty appearing in shopBug fixInternal playtestFix Osty intent disappearing after going to shop
- Implemented Osty animationsArtInternal playtestMinor change in Osty's size
- Osty's name now appears in attack intents
- Cards that have Osty deal damage but not you are now SkillsBug fixInternal playtestFix some issues around Osty's name
Internal playtest notes are from before the Early Access release. Names and numbers in them can differ from the game today.

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