Cloud's not expecting words of wisdom from Kuja, but his brow furrows slightly as he listens. Uncertainty can snatch failure from the jaws of success... Cloud feels as though his own experiences bear that out with uncomfortable accuracy, though he's not sure exactly why. "...mm. What if you can't assess your own skills, or...be certain of them?"

Cloud nods, holding out his hand to show Kuja the empty slot in his glove. "Crystallized mako, made into orbs you can mount in your gear. Gives you access to magic, summons, other abilities. Mako's what fuels everything - the 'planet's lifeblood.' Or at least, that's what some people call it."