Any chance of adding anti Infrared clothing in the future to reduce the players signature.
It may be necessary to add some sort of disadvantage to stop it from being used constantly, for example make it noisy, so you can’t stalk your prey too closely.
as infrared is heat , there could be cold pack suits but very heavy , stopping player from running.
just trying to add suggestions to your idea 
These have been around in the real world and tend to involve foil (and other) linings, but any suggestions to permit some balance to using them is worthwhile (we don’t actually want to get too real life do we 
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