Hello!
I have found it now after long time!

But the Jump Slash is buggy.
Don't know if for others too, but only my Character is spinning,
while the Weapon stands still,
with the slash-motion-frame until my character lands again.

I wonder if it fixes itself after a new start of the game.

@websurfer1111 It's looking like this problem is on your end, since the ability works as intended on my end. What does it say in the starbound.log file?

Hi!
Log-File_1 (82,4 MB) secured.
By entering 'cygnus' or the asset-ID into 'Control + F' I was only able to find out, that the mod got loaded.
No further results.
Do I have to search for something specific?

I made a video.
I'm restarting the game now, because it is still running since I wrote the first time, when I found the item.

Log-File_2 (458 KB) secured.
No change in behavier.
Cygnus keeps standing still, with the slash-frame, while the Jump-Slash playes.
Searching for 'jump' and 'slash' added no new informatin.

The same with a vanilla race (novakid, casual-admin-mode).

Now killed the first monsters with Cygnus.
The hit-box of the special-attack seems to be fine.
It seems to be only the animation.

@websurfer1111 Are there any error messages in the log?

More than enought errors, because I have a ton of mods installed.
But I guess taking a look for your self is here the best idea, because my best is to find out, what is causing my game to crash and remove the cause from my colection, followed by adding even more mods, when I'm already looking through the workshop XD.
How do you want me to give you the log-files?

@websurfer1111 the best way to do that would probably be through pastebin.

I was afraid you would write pastbin.
I'm on it.

I wasn't able to create a pastebin for
Starbound-Log-Cygnus_1. Pastbin couldn't handle it. It was too much.
But I was able to create a pastebin for
Starbound-Log-Cygnus_2: https://pastebin.com/W7PcHGG5