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Often, the actor's reaction statement will repeat their identification like ☶ in ☶: +☶.  This is because the reaction of the actor is reflexive, in other words, it must be thought in the context of the actor.  For example, one actor's sad might just be another actor's normal :.  The repeated instance of the identification is the avatar.
Intensity
☶ as a reaction can mean many different things.  However, in #acktueli, most of the time it is used as some basic acknowledgement.  An example to think of is if someone asked was asked a question, and to say yes or no, they said their name... like a pokemon.
Pikachu:
☶ *pika*
☶☶ *pikapikapiiika*
++☶☶☶ *pikaachooooooo!*