There are no quests in game with 300 kills xD
max. is 200 from lvl 90 to 105
Not entirely true, there are quests with 300+ kills in the game, maybe not from lvl 90-105, but higher than that and there is one with 600 (4 different mobs of 150 each), of course the exp is nicer for it as well, but running around and getting 300 tornado kills...yuck. Also one with 150 each of 2 mobs of ones in garden of mansion. May be more, but those are ones i remember atm. The ridiculous amount of drops in some is what i hate, not to mention they don't stack beyond 50 and one is over 100 drops of one item.