There is only a single Lunasaur in the 3D Remake, and it often opens with Bad Breath and will use it almost every turn, although it sometimes uses a physical attack instead which has the chance to cause instant death. Once struck with a physical attack, the Lunasaur begins an attack pattern more similar to its original counterpart, namely casting Reflect on itself and reflecting Bio spells onto the party. As it has Reflect, Rydia must resort to summoning Bahamut or Ifrit to hit the Lunasaur's weakness, but this causes it to counter with Heal to restore a portion of its HP. Once the Reflect it has cast on itself wears off, Lunasaur lapses back into the pattern of using Bad Breath almost every turn until struck by a physical attack, at which point the pattern begins again.
A simpler strategy is to repeatedly use Elixirs on the Lunasaur hitting 9,999 per use. To facilitate this, certain armors can be equipped to deter the effects of Bad Breath (e.g. Headbands, although weak in defense, prevent confusion).
An effective way of dealing tons of damage to Lunasaur is to have Rosa with Omni-casting and dual-casting then casting reflect on the party followed by Curaja for every other turn. With this strategy, Lunasaur should fall in three turns provided that the Curaja spells all do 9,999 damage.
Luna means "moon" in Latin, Italian, Romanian, Russian, and Spanish.