I used to kill blob all day, my times are based off EST
It spawns every 4th hour of the day 4,8,12 and it can spawn 1hour ahead of that time or 1hr behind it. Ex. For the 12a.m spawn it can spawn from 11 to 1
Loot wise it drops gralats.. a lot, 4 frog mounts, a slime pet, 4? hats and I think that is it