Cross-slash is a physical attack that consists of a lunge forward and three slices of Cloud's sword that forms a "凶", the kanji for "bad luck" or "evil/wicked". Despite the animation involving three slices, it only deals damage once.
Cross-slash is obtained by performing Braver eight times. This can be sped up by equipping Cloud with the Cover Materia, causing him to take more damage in battle, increasing his Limit gauge, and giving him more opportunities to perform Braver. Cloud can also use a Hyper to fill his Limit gauge faster and use Braver more often.
Cross-slash deals damage at 3.25 times Cloud's damage. In addition to dealing damage, Cross-slash inflicts Paralyzed on enemies not immune to it. This status effect freezes an enemy on the spot for a short while. Cross-slash can therefore be used to cripple a larger opponent while the party focuses on smaller enemies, or to quickly finish off an enemy to reduce the threat overall. Because it deals physical damage, it relies on Cloud's Strength stat and his currently equipped weapon when determining damage.
Cross-slash is the best level 1 Limit for Cloud, meaning if the player wants to fill Cloud's Limit gauge as quick as possible, Cross-slash is the best ability to use. It is also the only Limit Break for Cloud that can paralyze enemies. However, later Limit Breaks for Cloud are considerably more powerful, able to deal more damage in a single turn, making it worth the trade off to just equip a higher level Limit.