TNT

TNT acts like a normal block in Creative. However, in Survival it behaves like the Creeper's explosion. Upon being struck by the player, it will start smoking and flashing white. If there are no blocks to hold up the TNT block, activating it will make it affected by gravity and it will fall. After a few seconds, it explodes, destroying a vast amount of blocks, mobs that are nearby, and even the player if they are not careful. Hitting it a second time in Survival will stop the countdown and make it so you can pick it up to use later. TNT can clear water and lava. Setting TNT on fire activates it after a while. However, if the TNT falls in water, the explosion will not destroy any blocks at all but still cause damage.

TNT will damage surrounding blocks depending on what blocks are directly touching it or not. Empty space will create a larger destructive radius, while a TNT block completely surrounded by rock will destroy an exact 3x3x3 cube from its center. Obsidian doesn't have a set area affected by explosions. The resulting hole will not follow a certain pattern and strange effects are caused by enclosed Obsidian explosions.

This trick can be abused to mine out long 3x3x3 hallways without using your valuable pickaxe.

Since the Redstone update, TNT monster traps can now be created and used successfully, making TNT a valuable resource and a powerful defense. When exposed to a current, the TNT activates as if it had been activated by a player. Combine this with a Pressure Plate and you can create an automatic defense for your buildings (Although a one-time-use, as the TNT needs to be replaced).

Mining
Some ores that get caught in the explosion will drop resources. Generally, any ore that does not drop a block you can place will drop resources. This means that iron ore and gold ore will be lost if caught in an explosion, but flint, coal, redstone and diamond not. However, a block of redstone ore will only drop one unit redstone dust instead of the usual four-to-five.

Bugs

 * Activated TNT will not explode when hit by other TNT; it will simply be affected by the blast force. This can be abused to create TNT Cannons.


 * Arrows attached to TNT will fall off when activated. This can also be abused to create arrow cannons. These are probably not intended.

Explosion Strength
Different materials have different strength values against TNT. Most commonly referenced is Stone or Cobblestone, which both have a strength of 1, meaning that if you enclose a TNT in a 3x3 block of stone or cobblestone, the TNT will only destroy the stone and nothing else around it. Log has a strength of 2, meaning that if you enclose a TNT in a 5x5 block of Logs, it will only destroy the logs and nothing else around it. Sand has a strength of 3, meaning that if you enclose a TNT in a 7x7 block of pure sand, the TNT will only destroy the sand and nothing else around it. The strength values go like this:


 * Obsidian: 0
 * Adminium (Bedrock): 0
 * Brick: 1
 * Cobblestone: 1
 * Smooth Stone: 1
 * Plank (wood): 1
 * Iron (block): 1
 * Mob Spawner: 1
 * Log: 2
 * Cloth: 2
 * Dirt: 3
 * Sand: 3
 * Clay (block): 3
 * Gravel: 3
 * Snow (block): 4
 * Glass: 4
 * TNT: 4 (Meaning, one exploding TNT, will activate all other TNT in a 4 block radius)