Blizzard and Boulder

We have the Breeze, the elemental of wind, and the Blaze, the elemental of fire, but what about water and earth? We need to have two more to even it out! Here's my proposal:

The Blizzard:

Spawns in cold biomes such as the ice spikes biome, and is made of ice and/or snow. This mob would move at a slow pace and hurls powerful snowballs or icicles at you when you get close, firing them decently fast. It could also turn water to ice when it is near. It would drop Blizzard Rods which could be used for crafting ice charges, which could be some form of more powerful snowball, similar to what the Blizzard itself throws.

The Boulder:

Spawns in lush caves or dripstone caves and moves slowly, the opposite of the fast Breeze. It throws some form of boulder at you which has high knockback, and can roll into a ball and spin in a direction. It would drop Boulder Rods (earth rods?) which could be used for crafting earth charges, which could be used to turn you into a spinning ball, similar to what the Boulder does.

All four elemental charges could be used for creating some sort of enchantment or item. Having all of the elements would add cool new aspects to the game.