You mean the skills like Atk Up, Health Up etc and such.
You are also sure it's because of them?
Also where is the game lagging? Only in battle, on the world map, all places?
I definitely will take a look into it!
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Yeah i tested it out myself right now and they definitely seem to be the cause.
I am preparing a fix right now that disables those passive skills until I found a proper fix.
It will remove the passive skills for now but fixes the lagging, will be up in a few hours. With that your save should run normally again.
Thanks for finding!