Commands:
/slfr- reload command
/ls - leader board
/ls gui - leader board in gui
/heart - grab your heart
/addheart - add 1 heart
/addheart <player> - add 1 heart to player


Permisions:
slf.add - /addheart perm

PlaceholderAPI placeholders :
%simplelf_maxhealth% - your max health


Heart crafting
(apply custom textures to the structure block to make it a heart)