I generally don't make it obvious until the first minion is hit. From then on there's no point hiding it.
However, I'm also a devious bastard. I got a bit tired of the whole, "Ok, these miniatures all look the same and are minions, wizard..." thing. So I used the same miniatures for minions and standard monsters and made the stats and abilities basically the same.
Man, you should've seen the reaction from one player in particular. It was golden. "OMG! That guy just hit me for 15 damage and there are eight of them!" "What? It's just a minion? A level-appropriate minion can't do that much damage!" "Huh? Wtf? Why didn't they all die with that area effect attack?"
Good times.
However, I'm also a devious bastard. I got a bit tired of the whole, "Ok, these miniatures all look the same and are minions, wizard..." thing. So I used the same miniatures for minions and standard monsters and made the stats and abilities basically the same.
Man, you should've seen the reaction from one player in particular. It was golden. "OMG! That guy just hit me for 15 damage and there are eight of them!" "What? It's just a minion? A level-appropriate minion can't do that much damage!" "Huh? Wtf? Why didn't they all die with that area effect attack?"
Good times.