#8 arena does not use DB MOBs

[rock808]

When fighting in the arena, Phaos generates temp MOBs
rather
than pulling from the database. This will cause some
problem
with Mass Effect spells, since the "other" temp MOBs don't
really get generated until after the first is killed.

For now, I'm just reducing their max/starting HP which is
pretty much going to get the same results, but ultimately
this should be handled better.