Ran a singleplayer downfall run but with the mod enabled.
Using the NOB card causes the game to crash.
Stack trace mentiones Together in spire so I thought it might be a bad interaction between the two.
Disabling Together in spire, I can use the NOB card.

Relevant logs:

12:11:44.936 INFO basemod.BaseMod> publish on card use: Gremlin:Nob
12:11:45.486 INFO basemod.BaseMod> publish on post power apply
12:11:45.487 INFO basemod.BaseMod> powers modified
12:11:45.508 INFO core.CardCrawlGame> Exception occurred in CardCrawlGame render method!
12:11:45.509 ERROR core.CardCrawlGame> Exception caught
java.lang.IllegalArgumentException: Animation not found: idle
at com.esotericsoftware.spine.AnimationState.setAnimation(AnimationState.java:216) ~[?:?]
at skindex.modcompat.downfall.skins.player.gremlins.GremlinsAtlasSkin.loadOnPlayer(GremlinsAtlasSkin.java:103) ~[TogetherInSpire.jar:?]
at skindex.modcompat.downfall.skins.player.gremlins.GremlinsAtlasSkin$Patches$BecomeNobPatcher.Postfix(GremlinsAtlasSkin.java:161) ~[TogetherInSpire.jar:?]
at gremlin.characters.GremlinCharacter.becomeNob(GremlinCharacter.java:144) ~[?:?]
at gremlin.powers.GremlinNobPower.onInitialApplication(GremlinNobPower.java:36) ~[Downfall.jar:?]
at com.megacrit.cardcrawl.actions.common.ApplyPowerAction.update(ApplyPowerAction.java:268) ~[?:?]
at com.megacrit.cardcrawl.actions.GameActionManager.update(GameActionManager.java:179) ~[?:?]
at com.megacrit.cardcrawl.rooms.AbstractRoom.update(AbstractRoom.java:325) ~[?:?]
at com.megacrit.cardcrawl.dungeons.AbstractDungeon.update(AbstractDungeon.java:2532) ~[?:?]
at com.megacrit.cardcrawl.core.CardCrawlGame.update(CardCrawlGame.java:876) ~[?:?]
at com.megacrit.cardcrawl.core.CardCrawlGame.render(CardCrawlGame.java:423) [?:?]
at com.badlogic.gdx.backends.lwjgl.LwjglApplication.mainLoop(LwjglApplication.java:225) [?:?]
at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:126) [?:?]
12:11:45.512 INFO core.CardCrawlGame> PAUSE()
12:11:45.513 INFO core.CardCrawlGame> Game shutting down...
12:11:45.513 INFO core.CardCrawlGame> Flushing saves to disk...
12:11:45.513 INFO core.CardCrawlGame> Shutting down controller handler...
12:11:45.513 INFO core.CardCrawlGame> Shutting down publisher integrations...
12:11:45.513 INFO helpers.FileSaver> Save thread interrupted!
12:11:45.514 INFO helpers.FileSaver> Save thread will die now.
12:11:45.514 INFO helpers.FileSaver> Save thread will die now.
2024-06-06 15:11:45,514 FileSaver ERROR An exception occurred processing Appender Console org.apache.logging.log4j.core.appender.AppenderLoggingException: java.lang.Error: Interrupted attempt to acquire write lock
at org.apache.logging.log4j.core.config.AppenderControl.tryCallAppender(AppenderControl.java:165)
at org.apache.logging.log4j.core.config.AppenderControl.callAppender0(AppenderControl.java:134)
at org.apache.logging.log4j.core.config.AppenderControl.callAppenderPreventRecursion(AppenderControl.java:125)
at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:89)
at org.apache.logging.log4j.core.config.LoggerConfig.callAppenders(LoggerConfig.java:542)
at org.apache.logging.log4j.core.config.LoggerConfig.processLogEvent(LoggerConfig.java:500)
at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:483)
at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:417)
at org.apache.logging.log4j.core.config.AwaitCompletionReliabilityStrategy.log(AwaitCompletionReliabilityStrategy.java:82)
at org.apache.logging.log4j.core.Logger.log(Logger.java:161)
at org.apache.logging.log4j.spi.AbstractLogger.tryLogMessage(AbstractLogger.java:2205)
at org.apache.logging.log4j.spi.AbstractLogger.logMessageTrackRecursion(AbstractLogger.java:2159)
at org.apache.logging.log4j.spi.AbstractLogger.logMessageSafely(AbstractLogger.java:2142)
at org.apache.logging.log4j.spi.AbstractLogger.logMessage(AbstractLogger.java:2017)
at org.apache.logging.log4j.spi.AbstractLogger.logIfEnabled(AbstractLogger.java:1983)
at org.apache.logging.log4j.spi.AbstractLogger.info(AbstractLogger.java:1320)
at com.megacrit.cardcrawl.helpers.FileSaver.run(FileSaver.java:31)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.Error: Interrupted attempt to acquire write lock
at javax.swing.text.AbstractDocument.writeLock(AbstractDocument.java:1349)
at javax.swing.text.AbstractDocument.insertString(AbstractDocument.java:701)
at javax.swing.text.PlainDocument.insertString(PlainDocument.java:130)
at com.evacipated.cardcrawl.modthespire.ui.MessageConsole$ConsoleOutputStream.clearBuffer(MessageConsole.java:226)
at com.evacipated.cardcrawl.modthespire.ui.MessageConsole$ConsoleOutputStream.handleAppend(MessageConsole.java:183)
at com.evacipated.cardcrawl.modthespire.ui.MessageConsole$ConsoleOutputStream.flush(MessageConsole.java:154)
at java.io.PrintStream.write(PrintStream.java:482)
at org.apache.logging.log4j.core.util.CloseShieldOutputStream.write(CloseShieldOutputStream.java:53)
at org.apache.logging.log4j.core.appender.OutputStreamManager.writeToDestination(OutputStreamManager.java:250)
at org.apache.logging.log4j.core.appender.OutputStreamManager.flushBuffer(OutputStreamManager.java:283)
at org.apache.logging.log4j.core.appender.OutputStreamManager.flush(OutputStreamManager.java:294)
at org.apache.logging.log4j.core.appender.AbstractOutputStreamAppender.directEncodeEvent(AbstractOutputStreamAppender.java:199)
at org.apache.logging.log4j.core.appender.AbstractOutputStreamAppender.tryAppend(AbstractOutputStreamAppender.java:190)
at org.apache.logging.log4j.core.appender.AbstractOutputStreamAppender.append(AbstractOutputStreamAppender.java:181)
at org.apache.logging.log4j.core.config.AppenderControl.tryCallAppender(AppenderControl.java:161)
... 17 more

12:11:45.516 INFO core.CardCrawlGame> Flushing logs to disk. Clean shutdown successful.

Game crashed.
Version Info:
- Java version (1.8.0_131)
- Slay the Spire (12-18-2022)
- ModTheSpire (3.30.3)
Mod list:
- basemod (5.54.1)
- stslib (2.11.0)
- coloredmap (2.4.1)
- downfall (5.1.2)
- HighlightPath (0.0.3)
- spireTogether (6.4.15)

Mods in stacktrace:
- downfall (5.1.2)
- spireTogether (6.4.15)
Cause:
java.lang.IllegalArgumentException: Animation not found: idle
at com.esotericsoftware.spine.AnimationState.setAnimation(AnimationState.java:216)
at skindex.modcompat.downfall.skins.player.gremlins.GremlinsAtlasSkin.loadOnPlayer(GremlinsAtlasSkin.java:103)
at skindex.modcompat.downfall.skins.player.gremlins.GremlinsAtlasSkin$Patches$BecomeNobPatcher.Postfix(GremlinsAtlasSkin.java:161)
at gremlin.characters.GremlinCharacter.becomeNob(GremlinCharacter.java:144)
at gremlin.powers.GremlinNobPower.onInitialApplication(GremlinNobPower.java:36)
at com.megacrit.cardcrawl.actions.common.ApplyPowerAction.update(ApplyPowerAction.java:268)
at com.megacrit.cardcrawl.actions.GameActionManager.update(GameActionManager.java:179)
at com.megacrit.cardcrawl.rooms.AbstractRoom.update(AbstractRoom.java:325)
at com.megacrit.cardcrawl.dungeons.AbstractDungeon.update(AbstractDungeon.java:2532)
at com.megacrit.cardcrawl.core.CardCrawlGame.update(CardCrawlGame.java:876)
at com.megacrit.cardcrawl.core.CardCrawlGame.render(CardCrawlGame.java:423)
at com.badlogic.gdx.backends.lwjgl.LwjglApplication.mainLoop(LwjglApplication.java:225)
at com.badlogic.gdx.backends.lwjgl.LwjglApplication$1.run(LwjglApplication.java:126)