Near 2:55 one of your gems near the southeast side of the rock where the monsters spawn, goes crazy, it turns black and shifts through the shapes of the 6 shapes of gems and stays black with red glow.
Another one or two eventually do too, look at the Victory screen to see them if you can't while the video is showing the game, any idea what happened?
I kind of wish that in order to unlock the "hidden" levels there was a glowing fame score like in GemCraft Ch 1. However, I rather like the different battle modes in this version, and I guess it's hard to have a glowing fame score within though. Especially if one has the "x3" bonus. Anyway, I'm just going through the first tier finishing up all the battle modes. I rather enjoy the Arcane Guardian Battle mode. Tis a lot easier than expected, however I'm going to assume that given it's the first tier, it's going to be a whole heck of a lot easier XD Especially being a level 69 LOL.
@sense if u still havent passed the lv before the 1st arcane guardian you can decrease resonance and give the points to make the replenish skill mastery.And make sure that you have 2 grade 4 lime gems in the last 6 waves.It's very useful to get rid of the overwhelming monsters.