Unfortunately, his control over the earth isn't quite as fine, or as strong, as he might hope for. While he manages to impale the cat, it's, apparently, a lot heavier than it looks, and its frantic scrabbling rips through the spikes with surprising ease, its claws actually leaving deep gouges in the earth, quickly weakening it and letting the maddened creature rip free, and continue recklessly throwing itself towards him.