1.: I don't really know, you should probably ask Richardd or Donnie. We were killing them instead of trying to take them to the tunnel.
2.: I think it was six AMII will take them to 15%, but when you're doing a gaIII the damage it does is reduced. On 8 targets, it counts for about half of an AMII. The magic resist on Impossible to Guage mobs factors in here as well. 10 is definitely not enough to do it.
If you want to ga them all down, there are two ways to approach it. Get around 17 BLM for a single timed GaIII. Your PLD/DRK or whatever other puller you're using will have to CFH on the lamp (s)he pulls. The other option, that is less resource intensive, is using around 12-14 BLM to do a series of 6 BLM doing gaII then all BLM doing gaIII. This is more difficult, but is more feasible in many cases.
3.: Nobody knows at this point. In BtL's pre-patch attempt, it seemed that a combination of lamps and avatars were re-summoned at 75%. In the latest Apathy attempt, it seems only the avatars were re-summoned although I can't be sure of this considering they won't say anything. It does seem feasible though because the number of Pandemonium Lamps in the DATs went from 30 to 17. 17 accounts for the original 8 lamps as well as the 9 avatars, but they can reuse the same DAT files so it doesn't mean too much.
Nobody has taken it below 75%, the 'every 25% HP' behavior is assumed.
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