Characters that have constellation cards equipped are experiencing the debuffs (slow, -attack%, -flee% etc) from every constellation card they have equipped on themselves!
This is seen in the various dungeons, towns, challenge, pvp areas etc. Thankfully it doesn't happen in auto-hunt world maps.
If you take out the constellation cards then the effect no longer applies. This completely defeats the point in having these cards... if you get the debuffs as well as your opponent.
It also makes the challenges difficult.
Also, there are still many more bugs, incorrect descriptions with the cards etc. Sagittarius card makes the helm no longer show up for example.