Not to be pedantic here but this is my area of expertise.
Mob HP in EQ ramps up considerably around NPC level 40. LDCs have a non-trivial amount of hitpoints. On live servers it's ~5550 and in old EQ it was a little less at ~5250. On top of that, melee DPS in classic era was rather weak. Melee DPS ramped up considerably in Kunark with higher skill caps and much better weapon ratios. (Karnors dropped weapons equivalent to classic god loot) In classic era, melee damage output was somewhere in the neighborhood of 25 DPS at level 50 with raid weapons.
Even a wizard chain casting his level 39 nuke with no resists would take well over a minute to kill a LDC assuming no modern additions or resists. (resists would be highly likely on a yellow) 7.5 seconds per cast times 405 damage = 54 DPS = 13 casts to do 5265 damage = 98 seconds. 405 is the damage of the spell at level 45+ so technically it would be doing a little less if the spider were yellow con.
