if player get damage he will drop redstone.
Just add the plugin and go to the config and change the ratio
---
#Redstone drop ratio of 100 (%)
RsDropRatio: 30%
RsCanPickup: false
SpecificItems:
enabled: false
items: ["Diamond Sword", "Diamond Axe"]
SpecificWorlds:
enabled: false
worlds: ["World"]
...