Bukkit

5.1.0

• changed: setting any mob droprate to a negative value now causes the plugin to ignore the death event and permits vanilla behavior.  This extends from the behavior of the negative witherskeleton droprate added in 3.12 as this would produce simpler, more uniform configuration that better handles future situations.
  
• added: added drop rate modifiers for slimes and magmacubes based on their size. Previously, all sizes of slime received the same droprate. In the configuration file these are numbered 1-4 for the size of slime provided by Bukkit, where 3 does not spawn naturally (corresponding to 0-3 in Minecraft) under the configuration section slimemodifier. The default modifier for each size is 1.0 to maintain behavior of previous versions. These values are multiplied against the base droprate for the mob as follows:

Effective Droprate = mobdroprate * slimemodifier * (1 + lootingrate*looting_enchantment_level)