Original Post — Direct link

The difference between using the actual Slayer Master Cape and Using a Different cape that has the passive perk put into it is Night and Day.

The 20% Chance to pick your own task Happens WAY more often on the actual cape and is virtually non existent if you perk a cape with it.

I don't care what anyone says, if you actually do slayer and have the cape in your max/comp capes then you also must've noticed the difference too.

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over 5 years ago - /u/JagexBreezy - Direct link

From a quick initial look you appear to be right, funnily enough setting my "luck" does actually seem to make it work. In which case it might be that you have less of a chance with it attached to a cape? Which sounds very weird if so. Regardless i've made a job to investigate it and other capes such as the Invention master cape which someone mentioned in the comments here and get it sorted if it is a bug.