AWKWARD ZOMBIE

So there's no escape besides hacking bedrock

It's official I am never playing anything besides peaceful

You can break bedrock as well, but it takes a crapton of TNT to do so. You have to make sure a lot of it lands at the same spot so it detonates by the wall...

I just wrote up the "new" mob and I would never play on anything but Peaceful if this was put into the game.

Name: Sleeper in the Dark

Damaged By: Light

Encountered: Rarely when mining deep in the earth, from level 6 to 0, you will open up a pitch black room. Entering it will cause the message, "The Sleeper in the Dark has been awakened and not even the light will save you now," to appear on your screen. At this point the Sleeper will spawn in the room in one minute.

Behavior: Once spawned, the Sleeper will lock onto the player who entered the room and begin pursuit no matter where he is in the world. He will favor any pre-made tunnels made by the player but if necessary will make his own. In addition he will automatically extinguish ANY light source other than the sun in a ten block radius from him. He moves slightly faster than the player, so don't expect to outrun him if you are caught unawares. In addition, he can break blocks as if his melee attacks were of diamond quality. At night he will ascend to the overworld if that is where the player is and go back underground just before dawn, still continuing his pursuit.

Damage: The Sleeper kills instantly.

Strategy: If you awaken the Sleeper at night then the best strategy is to run back home as fast as possible and begin fortifying with the strongest blocks you have. Though light damages the Sleeper, don't bother with torches, glowstone, or netherrack as the Sleeper will extinguish them automatically when he gets in range. They can make for a good warning system though.

The key to beating the Sleeper is to get it to pursue you to a place where getting hit by sunlight is its only option. This means no blocks it can tunnel under. Sky houses and fortresses are good options if you feel confident in knowing your structure well enough to stay ahead of the Sleeper once its inside. Iron doors and switches will buy you enough time for this.

Loot: Who knows.

Bonus: The room where the Sleeper spawned is always active. Entering it again, or someone new wandering in, will spawn another Sleeper.

No, you cannot

What if those new mobs are like pranksters? They take blocks from the overworld and rearrange them in pre-made patterns and buildings. If you find them in the middle of building, they flee and leave whatever they're holding.

They already creep me out. I hope they're not aggressive.

it would be neat if they did that in fixed locations, starting as soon as a world is generated, and they build relatively large and complex structures, but if you scare them off they never come back and that specific structure will just sort of sit around incomplete, with exposed treasures everywhere
If you explore that area really late in the game, though, you get to actually go through it and find some really cool item at the end.

Anything but what Madican wrote is fine for me. As long as they never attack you. Because I'm as spooked by Skeletons and Zombies as it is.

I think it would kinda ruin the game if they took blocks from your house, though. But that's just me. Maybe it would go with the whole "Lose everything, suck it up" thing they put us through with dying and what Notch is planning with the new Exp. system.

Another Idea for the new thing
Different Player builds.
ORIGINAL: Looks like the original player model. Holds blocks with one hand.
HEFTY: Looks like the original player model with cubes on his body to resemble muscles. Holds blocks with one hand.
SPOOKY: Looks like the new mob thing. Holds blocks with two hands.

Double post but those new mobs are called Endermen
AKA Slendermen

And so my ideas for the mob seem much more valid.

Your silly pranksters do not exist. Only those that lurk in the darkness.

I am so looking forward to this new mob

make it so it drops a full diamond item on death, it never respawns, and slightly slower than the player and yeah that'd be cool

otherwise never play minecraft ever again

I'm not entirely comfortable with a lot of the changes being made to Minecraft lately; The thing about permadeath is especially disconcerting, though the return of a creator mode effectively separates two different styles of play within this game.

I'd probably have a creator mode file and a separate adventure mode file - in which case I wouldn't be so heartbroken if I did suffer a permadeath.

Permadeath is optional - It's like 'Hardcore' mode in Diablo II/Torchlight from what I understand.