Ok, ran a playtest of the class tonight, adding in a vigilante to the party to help out with their current mission. A little bit of GM Fiat got him into the group (THey are going into the jungle, and thus needed a guide. And so their backers sent them a 'wandering gnome' guide!) So, the little talkative gnomish man is leading them through the jungle when they come across a huge beastie thing that wants to kill us. The party is fairly stacked, and highish level (14th), so it's not too hard of a fight. Brini the gnome jumps into a bush, having previously told them he's not much of a fighter, 'hid' there they whole fight. After the first round, a masked and armored Gnome showed up, slinging mystic bolts, and doing a decent job of helping out. (He was by far the lowest damaging dude on the map, but that will go into the playtest feedback forum later!)
ANYWAY, after the fight is over, we got to talking a bit, and they were wondering where this mysterious figure came from. My guy bluffed his way out of it, saying he didn't see anyone, so that person must have run off! Fine enough for just some fun! BUT, then we got talking.
We know divination spells wont work to figure out Brini the Wandering Gnome is also the masked vigilante (Name TBD, so if you're part of my group, I'mma leave you guessing!). But... what about arcane mark? They could slap an invisi one on his forhead, and then forever (For a month at least) tell that Brini is also the masked man. A 0th level spell completely negates the 'special thing' for the entire class. Did I miss something, and there is actually something in the class that helps (Outside of the dispell/arcane mark of your own combo my Warlock thought to do).
Anyway, something to think on maybe!
