so, the way i see it we should give some of our ideas to notch just post your mob ideas and we can signal notch to see our mob ideas and he might use our ideas my ideas are

1 cyborg:
* can fly 1 slab above the ground
* neutral unless spawn at night
* craftable
*self-destructs if on fire

2 earth worm
* 5 blocks long
* 4 blocks tall
* burrows 10 blocks down
* sand biome boss
* swings its head to attack
* the tail is the most vulnerable spot

3 burrowers
* burrows underground
* attacks you by silently popping up behind you and biting you
* they sound like chattering teeth
* have a big jaw sharp claws and sorta human-ish
* its as slow as a sprinting ocelot
* deals 3 and1/2 hearts per hit
* can not burrow through wool,cobblestone, ores, iron blocks, water, diamond blocks, gold blocks and all nether blocks (i forgot to mention end stone, obsidian and bedrock)
* body is made up of mostly 87% indestructible iron making it immune to lava
can burrow 2 blocks up other than that it will fall back down
* the player can crawl through the burrower's holes that he makes