I rapidly clicked on the block icon to build spell back up, then hit him again, and again.
Again, by continuously and rapidly clicking on the icon 4th from left, to max out the purple bar, then clicking the batterang, and quickly rapidly clicking on the 4th icon and repeat. Anyhow, the various worlds and pretty colors just aren't logical for this game. It's clearly a photo shop rendering. Nice try guys, I just don't buy it ! ! !