I did some some research on the Creature Illusion spell and saw that Tibia wiki lists it as a rather useless spell, more for show purposes as it has no impact on game play. I also note though that once you use the spell, it removes the speed increase from mounts and won't let you mount until the spell dissolves. This led me thinking that the spell actually inadvertently has a negative impact on game play. However, I decided to do some testing and saw there is one creature that I found which actually gives you a rather large radius of free blue light (check screen shot below), the Jellyfish! I was wondering if there were any other hidden perks/features that can be used from this spell?
There are a few more uses. As already answered, and probably the most useful one, is to disguise yourself in PvP situations. Other uses are:
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