I have seen Endermen pick up grass blocks, but I want to know what all blocks they can pick up and what blocks they can't pick up.
This is no longer relevant for the current version of Minecraft, but in Minecraft Beta 1.8.1, Endermen were able to pick up and any solid, entirely cubic block except the following:
- Any double slab
- Monster spawner
- Note block
- Piston and sticky piston
- Snow block
They can, however, pick up the following blocks which are not entirely solid cubic blocks:
- Flower (both types)
- Mushroom (both types)
Notably, tilled farmland is not a full height block and the Endermen cannot pick it up, but if they walk on it, turning it back into a dirt block, they can pick up that dirt block. Likewise, Endermen cannot pick up stairs (any type), half slabs (any type), fences, doors, gates, iron bars, cobwebs, beds or cake.
Endermen cannot pick up things attached to blocks, such as buttons, ladders or redstone wire. However, they can pick up the block it is attached to, which will cause the attached thing to drop as if the block was destroyed.
Endermen can pick up both naturally occurring blocks and blocks placed by players. In the Minecraft 1.8 pre-release they were able to move bedrock, but as of Minecraft 1.8.1 this was no longer possible. They cannot pick up water or lava.
As of MineCraft 1.7.4, the following are the only things Endermen are allowed to pick up:
- Flowers (red and yellow)
- Mushrooms (brown and red)
Endermen from what I've seen and heard can pick up most types of blocks including natural and player-placed blocks, chests, furnaces, noteblocks, mob spawners, obsidian, and bedrock. There appear to be some types that they cannot pick up, but there is not yet any final list of these.
A user on the Minecraft forums gives an account of an Enderman picking up his chest, causing the items to burst out everywhere (as I commented extensively on Sir_Tiffy's Reddit thread, chests cannot be moved with their contents intact for the same reasons pistons cannot push them).
I'd post more links but the spam prevention won't let me since I don't have any rep yet.
Endermen will only pick up and move certain blocks, regardless of whether they were natural or placed by the player. They will pick up blocks horizontally and vertically nearby, within a short reaching distance similar to the player's (3 layers). Endermen will not drop the block they are holding when enraged or slain. It will simply disappear,
According to http://www.minecraftwiki.net/wiki/Enderman an enderman can only pick up:
grass blocks, dirt, mycelium, sand, gravel clay, dandelions, rose, brown and red mushrooms, cactus, pumpkins, melons, and TNT.
Endermen cannot pick up entities, such as boats, minecarts, primed TNT, and mobs.
Enderman can pick up any full block, except obsidian. They cannot pick up transparent blocks such as glass, glass panes, stairs, half-slabs, etc.
Enderman can pick up simple items like dirt, stone, brick, ores, ect. I have seen them carrying flowers, but they are mostly spotted with dirt or, when in caves, stone. They can not pick up obsidion or bedrock, and they do get mad at blocks that they can not pick up. Clearly, enderman are the smartest mobs , and can actually outsmart steve. they can see up to 64 blocks away.
To summarize as well as I can from everything I've read, Endermen can pick up any NATURALLY SPAWNING block. It does not pick up blocks that exist only if a player has created it (I.e. any blocks that must be crafted with the crafting bench).