Have you tried the Dev.exe (located in your sins installation folder in case you're new to modding)? If yes, what error does it return? Including errors on startup that might be related to any of the files involved.

Does the first action trigger? You should see the Kostura charge up animation if it does. Does the last action trigger?

Have you registered everything in the entity.manifest?

Are you using Entr. or Diplo? If not the syntax of your buff is incorrect.

I've tried the Dev.exe, but it's getting hung up on an "i >= 0" problem (that doesn't crash the game) and there's no way to get past that infinite error to actually try the ability.  I have a feeling they may be connected, but no way to know for sure.

The first action and the last action both are triggering just fine.

As far as I can see, everything is registered in the entity.manifest.  Wouldn't the game minidump if it wasn't?

And yes, I am modding for Diplomacy.

1. Diplomacy.

2. If we can determine that this buff definitely isn't what's wrong, then yeah I'll put up the other two, but I figured we could get process of elimination going by checking this one for errors first.

3. Yeah, everything is in the manifest.

4. The buff (designed for a ship) is supposed to launch a cannonshell at a targetted orbit body (I have tested it with multiple cannonshells, none of them work), create a phase node at its own orbit body (BuffDiscoveryFTLLocalBody), and reduce its own phase jump speed by 300% (BuffDiscoveryFTLSelf).

This buff is able to play the Kostura powerup effect (the first action) and reduce the ship's phase speed by 300% (the fourth/last action).  However, the second action (launching a cannonshell) and the third action (creating a phase node at the local orbit body) don't work.  They also don't cause a minidump or any kind of visible error; the actions just never occur.

That is what it looked like originally.  I changed it because I needed the effect to base itself off of the Center point rather than an Ability point.  The cannonshell does not spawn with either setting.

As I said, I can't the Dev.exe to tell me where the error is because every time I run it, it gets spammed with "i >= 0" errors that don't tell me where the problem is.

The ability is intended for a capital ship, but I have quite a few other capital ship abilities that aren't configured for leveling, and they all work just fine.  I did check to make sure the proper meshpoints were in place, and they are.

I'll go ahead and put up the Ability file and the other buff for you.

TXT
entityType "Ability"
buffInstantActionType "ApplyTargettedBuffToSelfNoRange"
instantActionTriggerType "AlwaysPerform"
buffType "BuffDiscoveryFTL"
targetFilter
        numOwnerships 3
        ownership "Friendly"
        ownership "Enemy"
        ownership "NoOwner"
        numObjects 2
        object "Planet"
        object "Star"
        numSpaces 1
        space "Normal"
        numConstraints 0
effectInfo
    effectAttachInfo
        attachType "Center"
    smallEffectName ""
    largeEffectName ""
    soundID ""
needsToFaceTarget TRUE
canCollideWithTarget TRUE
moveThruTarget FALSE
isUltimateAbility TRUE
maxNumLevels 1
levelSourceType "Intrinsic"
minExperienceLevelRequired
    Level:0 0.000000
    Level:1 0.000000
    Level:2 0.000000
aiUseTime "NotInCombat"
aiUseTargetCondition "Any"
isAutoCastAvailable TRUE
isAutoCastOnByDefault FALSE
pickRandomPlanetToExploreForAutoCastTarget FALSE
ignoreNonCombatShipsForAutoCastTarget TRUE
onlyAutoCastWhenDamageTakenExceedsPerc 0.000000
useCostType "AntiMatter"
antiMatterCost
    Level:0 100.000000
    Level:1 0.000000
    Level:2 0.000000
cooldownTime
    Level:0 120.000000
    Level:1 0.000000
    Level:2 0.000000
orderAcknowledgementType "ONGENERALORDERISSUED"
researchPrerequisites
    NumResearchPrerequisites 0
nameStringID "IDS_ABILITY_DISCOVERYFTL_NAME"
descStringID "IDS_ABILITY_DISCOVERYFTL_DESCRIPTION"
hudIcon "HUDICON_ABILITY_PHASEGATE"
smallHudIcon "HUDICON_ABILITY_PHASEGATE"
infoCardIcon ""

TXT
entityType "Buff"
onReapplyDuplicateType "PrioritizeOldBuffs"
buffStackingLimitType "ForAllPlayers"
stackingLimit 1
allowFirstSpawnerToStack FALSE
buffExclusivityForAIType "ExclusivePerPlayer"
isInterruptable FALSE
isChannelling FALSE
numInstantActions 0
numPeriodicActions 0
numOverTimeActions 0
numEntityModifiers 0
numEntityBoolModifiers 1
entityBoolModifier "IsPhaseGateEndPoint"
numFinishConditions 1
finishCondition
    finishConditionType "TimeElapsed"
    time
        Level:0 120.000000
        Level:1 0.000000
        Level:2 0.000000

Unfortunately, that didn't work.  And wouldn't the whole ability stop working if the problem was in the actual ability file, rather than in the buffs?

I read somehwere on this forum that the i>=0 errors mean you missed a quote in some file. (Which would cause the affected file to malfunction while not causing a minidump) Note however that they aren't infinite, at least if they're the same as the ones I get. I haven't managed to locate the source, but I get about 35 of them in a row. "Skip All" can skip through them iirc, if not just mash the button. You might even see a buff-related error after clicking through these. Keep playing until you use the ability once. Many errors are only recognised when you access a relevant file (i.e. String Not Found errors only occur when the string should be shown, not at startup)

The OnBuffFinish trigger works, as that's what the original Kostura uses. The Center reference should also work, as all stock meshes have that hardpoint. (and if a custom mesh doesn't it should get one immediately)

Try splitting each of the actions off from this buff into a seperate one, and replace the instantActions in this one with 2 ApplyBuffToSelf, triggered OnDelay after 0s. The CreateCannonShell might require a seperate buff (at least I've never seen it used alongside other instantActions in the same one)

Maybe give each of these new buffs a passive boost (armor/damage/whatever) to check which of them are even applied, then check which of them actually execute properly.

You could also try remaking the ability from scratch, copying only from unmodded reference files. Pay attention so you don't get any typos, and see if that works. If it does use this remade ability, if it doesn't you know the problem isn't caused by typos or similar errors.

I'm still having a ton of trouble with this ability.  I've gotten everything working now except for the cannonshell.  It still just won't fire, period.  As far as I can tell, this ability follows the pattern of the Kostura ability to the letter.  It also follows Zombies' BuffPlagueOrbitalCannon.entity exactly.