Intro:
Binded hero limit is set to 3 by default, because of this after choosing 3 bound heros the rest of the available binding heros disapper from the Hero Selection Menu(This is Normal, its supposed to do that). Hence you can't select more then 3 bound heros.
Bug:
If you select up to 3 bound heros and drop one bound hero while dead or in spectate you can continue selecting as many bound heros as you like and use them as well. So you can potentually bypass the restriction of ammount of bound heros.
(There is a cvar to change the ammout allowed to bind. I have not tested if the bug occurs when changing that limit, but I assume so.)
*Note* This is probably also why people keep asking "I added more heros but I can't choose them, why is that?". It might be because they have selected 3 binded heros and the new ones they added are of the bind type, tell them to say "/clearpowers" then check if they can see the newly added ones.
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