Cave Monster Expansion

Adds items: Soul (dropped from mobs, activated by holding), Ribbon Fang (used in spear crafting), Ribbon Skulk (used in Ribbon Spike crafting, dropped from Skulk Spiders), Fang (used in Ribbon Fang crafting, dropped from Skulk Spiders/Tails), Spear Top (used in spear crafting), Beetle Carapace (from Beetles, used in armor), Beetle Armor (grants Scarab strength), Amethyst Sword (powerful melee weapon), Spear (powerful melee weapon with area-denial ability). Spear abilities: melee attack with 5-block arena creation, damages all mobs 1 heart/second for 10 seconds, protects from projectiles (costs 10 souls); Amethyst Sword: sneak activation grants instant health 2 and saturation for 5 seconds (costs 5 souls). Includes new challenging mobs found underground.