KillBlock

public class KillBlock extends Block
{
    //Constructor
    public KillBlock()
    {
        super(Material.IRON);
        this.setUnlocalizedName("killBlock");
        this.setCreativeTab(CreativeTabs.BUILDING_BLOCKS);
        this.setResistance(5.0F);
        this.setHardness(5.0F);
        this.setLightLevel(0.1F);
        this.setHarvestLevel("pickaxe", 1);
    }

    /**
     * This method will return the bounding box of the kill block;
     */
    @Override
    public AxisAlignedBB getBoundingBox(IBlockState state, IBlockAccess source, BlockPos pos)
    {
        AxisAlignedBB axis = new AxisAlignedBB(0.0D, 0.0D, 0.0D, 1.0D, 0.875D, 1.0D);
        return axis;
    }

    /**
     * This method will check whether or not the block has been collied with vertically. If so, it will kill the
     * player if it doesn't have the protective aura.
     */
    public void onEntityCollidedWithBlock(World world, BlockPos pos, Entity entity)
    {
        //System.out.println("onEntityColliededWithBlock checkpoint 1");
        if (!(entity instanceof EntityPlayer))
        {
            //System.out.println("onEntityColliededWithBlock checkpoint 1a");
            return;
        }

        //System.out.println("onEntityColliededWithBlock checkpoint 2");
        EntityPlayer player = (EntityPlayer) entity;

        //System.out.println("onEntityColliededWithBlock checkpoint 3");
        if (!player.isCollidedVertically)
        {
            //System.out.println("onEntityColliededWithBlock checkpoint 3a");
            return;
        }

        else
        {
            //System.out.println("onEntityColliededWithBlock checkpoint 4");
            if (!player.isPotionActive(Main.auraPotion))
            {
                //System.out.println("onEntityColliededWithBlock checkpoint 5");
                player.attackEntityFrom(DamageSource.generic, 50);
            }
        }
    }
}