The most I've ever got is 5k on a x3 endurance just before first arcane battle (in placement, it was after I passed second arcane battle that I got it)
A lot of mana farming for insane mana gain, about 110 levels of mana pool (for 6,5x XP + even more mana) and using a lot of gems to anger monsters (for more monsters and about 3-4x score gain/monster). Having plenty of heavily boosted yellow-red-orange gems in traps helps quite a lot in getting mana. Each gem hits 6 targets at once has firing speed of 1071 and gives 8.6*6.65 mana/hit.
I could have done a lot more but I really got tired on all that lag it caused (I had only like 1-4 fps almost all the time with 3GHz dual core with minimum graphics settings).
WHAT. THE. HELL!? I think you just broke the game with that one.
I understand how they're doing it now. I got 11k on the third arcane battle. I summoned a LOT of giant monsters (so it looked like a SWARM wave) with a very powerful dual (orange-blue) with maxed out mana gain per hit, maxed out range and maxed out rate of fire. Took many of them two paths round to kill (but it fired SO QUICKLY that I easily covered the banishment costs. Had over 30k max mana t the end (I only had about 200 left, because I had spent it all on mana pool jsut before I killed the last arcane m,inion (that's right, it was so powerful it wiped the floor with the arcane guardian BEFORE the minions died) bumped me up to Bleeding Edge (I mean level 48. I say that because that's when Bleeding Edge mode is unlocked.)
I don't wanna know yet what I'll achieve at the gem itself.
Nope, it's legit. I mana farmed for 120 waves, angered a wave of Giant monsters to the point that there were 7000 of them, and then killed them all using the gem of eternity.