I'm trying to make a block that spawns an ender dragon when you jump on it and then destorys itself. In its current state, it spawns 2 ender dragons before destroying itself.

 

public void onEntityCollidedWithBlock(World worldIn, BlockPos pos, Entity entityIn) {

// TODO Auto-generated method stub

if(entityIn instanceof EntityLivingBase) {

EntityDragon test = new EntityDragon(worldIn);

test.setPosition(pos.getX() + 5, pos.getY() + 5, pos.getZ());

worldIn.spawnEntityInWorld(test);

worldIn.setBlockToAir(pos);

}

}

Always specify the version of Minecraft you're using in the title.

 

Block#onEntityCollidedWithBlock

is called on both the client and the server. Only spawn entities on the server (when

World#isRemote

is

false

).