Faster than Super Saiyan Vegeta while saving some of his energy in reserve

Vegeta dodged Cell's kick and responded with a feint-punch combo, but the monster managed to block and swing his tail around, sending Vegeta smashing against the ground. It was clear: he needed more power. The android, 17, had been enough of a challenge; not being able to sense the machine's energy and not being able to rely on his opponent tiring out had pushed Vegeta's martial creativity to its limits. But 17 had been nowhere near as strong as Cell. The insectoid beast had powered up much higher than Vegeta could match. Not since King Cold had Vegeta faced a fighter with so much raw strength.

- Bringer of Death Chapter 42

"Shall I show you a bit more of my power then, Vegeta? Perhaps that would do the trick." Cell laughed. It was somehow energizing and exciting to lay such a substantial bluff, but he played his part well. He had been saving a bit more strength: not enough to win, but enough to back up his boast. In the meantime, he also kept a constant focus on his surroundings—when the androids arrived, or if they already were present, it was vital he find them immediately.

The prince stood up, crossing his arms and smirking. "Let's see it…" he demanded, his confidence far surpassing Cell's.

"GRRRR…RAAAA!" shouted Cell, powering up as high as he could go. The strange monster somehow was able to produce the same golden aura that only the Super Saiyans were capable of...something that bothered Vegeta. More than ever, the prince wanted answers.

'His power continues to rise, but who IS he? I will find out before I end him!'

- Bringer of Death Chapter 43