Cid is an expert pilot and mechanic who dreams of one day becoming the first man in space.  His dream would have been fulfilled, but he aborted a launch in order to save the life of one of his crew.  Now he spends his time trying to repair his inoperable rocket in the hopes that Shin-Ra may one day reinstate its space program, giving him another chance at fulfilling his dream.

Level 1:  Boost Jump-- Cid vaults into the air and crashes down on a single opponent's head.  This is a straightforward attack that's your best bet for killing a single enemy early on.  Dynamite-- Cid produces a large stick of dynamite that he hurls into a group of enemies.  Once Cid learns the Dynamite Limit Break, it's unlikely you'll ever use the Boost Jump again.  It causes a fair amount of damage to each monster in a group, but the effect isn't cumulative like Big Brawl or Dragon Dive.
Level 2:  Hyper Jump-- Cid leaps into the air and drives his weapon deep into the ground, causing a huge blue explosion that damages an entire group of enemies.  This is basically a more powerful version of the Dynamite Limit Break; it's great against a group, but loses something against individual opponents.  Dragon-- Cid summons a dragon to attack one of his enemies.  The dragon injures the victim and transfers the Hit Points and Magic Points back to Cid.  This is the best Level 2 attack against a single creature.  It's also effective when Cid needs a small boost to his MP; the HP boost is insignificant.
Level 3:  Dragon Dive-- Cid repeatedly pounces on a group of opponents.  Each attack creates a large explosion that causes heavy damage to a single opponent.  The Dragon Dive is the Stronger of the two Level 3 Limit Breaks, but it connects against the enemy fewer times.  Big Brawl-- Cid shows off his fighting skills by leaping into a group of enemies and crushing them with a series of blazing-fast attacks.  The Big Brawl hits for less each time, but it hits more times than the Dragon Dive.  It'd difficult to say which attack is better.
Level 4:  Highwind-- After getting the submarine, locate the crashed Gelnika off the shore of the Gold Saucer.  Inside the cargo bay, you'll find Cid's Highwind Limit Break.  Cid calls on the Highwind for assistance.  The ship's crew answers by unleashing a huge salvo against the opposition.  This is a great attack against a single enemy or a huge group.  Each missile causes several thousand points of damage to most enemies, plus the total damage is cumulative.