Everytime I spawn a mob, about 10 minutes later they double

[pavis]

Im making a leveling road and im making 25 of each 5 lvl mobs and the mobs double themselves and its really anooying to go back through and delete them. How do i fix this?

[dfk789]

Spawn half the mobs you need? =/

[pavis]

They Spawn right on top of each other and cause lag to attack.....If u dont have a legit answer plz dont post

[LJN]

Glitch with rev happens to me too, if you restart your server there is only 1 when you log back on.