Monsutaari

A mod that aims to spice up some of Minecraft's monsterous mobs.

New mobs
Skeleton Head and Wither Skeleton Head: Hitting a Skeleton or Wither Skeleton has a rare chance to knock their head off. Their skull will hop at you, seeking revenge. Chance to drop a Skeleton/Wither Skeleton Skull.

Their body will panic not knowing what to do. 

Quartz Skeleton: A variant of skeleton with sharp quartz blades on its arms that spawns in the Nether Wastes biome. Their bones are so old that they've become Quartz! Hitting them with a pick-axe will make the quartz drop off. It can even be shot off with an arrow! After a while, the quartz will regrow.

Clay Cube: An aggressive Slime-like mob that spawns in rivers during phases of the moon when Slimes typically spawn. Has variant faces. You can cycle between them by right-clicking with a shovel. Drops clay.

Snow Cube: A passive Slime-like mob that spawns in snowy biomes during phases of the moon when Slimes typically spawn. Leaves a path of snow when it hops. Drops Snowballs.

Wisps: (disabled by default) These magical passive creatures spawn at night in Forest-y biomes. Touching one will bestow you with an effect, positive or negative. Right clicking them with a bottle will collect the type of effect they would've given you in the form of a Potion

New Mob abilities

Spiders: When attacking, they trap their target in a sticky web that will slowly decay over time. They will now hunt Silverfish and Endermites as their prey. 

Skeletons and Wither Skeletons: They have a chance to lose their head when being fought.

New Blocks

Block of Bones: A storage block for Bones (not to be confused with Bone Blocks, storage for Bonemeal!) They fall, much like sand or gravel, if there are no supporting blocks beneath them

Hanging Web: A decorational block crafted out of Cobweb

New Flowers

Golem Flower: A pumpkin-inspired flower planted on the spot where and Iron Golem or Snow Golem die. Can craft into yellow dye.

Wither Rose Bush: A two-tall variant of Wither Rose that is planted when a large mob or a mob with a large maximum health (30+) is killed by the Wither. Can craft into 2 black dye.

Marigold: A flower that spawns in Plains biomes (additionally can be found in Autumn-y biomes added by Autumnity / Biomes O' Plenty, if you use those!). Can craft into orange dye.

New Foods

Dubious Cake: A nasty cake crafted out of Wheat, Rotten Flesh, Ink Sacs, Bonemeal, and a Spider's Eye. Eating it will likely leave you with negative side-effects.

New Effects

Pumpkin Powered: When wearing a Carved Pumpkin while having this effect, hitting mobs will launch them into the air. Throwing Snowballs will have a chance of not consuming the snowball.

Obtained by repairing a Iron Golem or Snow Golem with iron ingots or a block of snow. Also can be brewed with an Awkward Potion and Carved Pumpkin.

Compatibility

Create: Crushers/Mills will produce greater amounts of dyes / outputs from the flowers added by Monsutaari

Autumnity: Marigolds can be found in certain Autumnity biomes.

Biomes O' Plenty: Marigolds can be found in Seasonal Forest biomes.