The Sacri chain is the only series of magic spells that can be cast outside of battle, and is one of few spells that can be used in ship battles without needing the Magic Cannon; in these battles they restore eight times what they normally would.
Sacri is the first Green spell learned. A feeble burst of life energy restores 500 HP to one ally. Costs 2 SP in battle, but is better used outside of battle. (Even then, it's better to use the other Sacri spells in order to conserve MP.) This spell usually becomes disused fairly soon as the game progresses simply because it is fairly weak.
When cast on a ship, Sacri restores 4,000 HP.
Sacres is the third Green spell learned. A bright burst of life energy restores 1000 HP to one ally. It costs 4 SP in battle, and becomes the mainstay healing spell for a large portion of the game (given that sacrum costs twice as much SP.) Sacres crystals (the item equivalent of this spell) are by far the most common healing method until Sacrulen is reached.
When cast on a ship, Sacres restores 8,000 HP.
Sacrum is the fifth Green spell learned. A strong burst of life energy radiates from all party members, restoring 1000 HP to all characters. This spell will not heal unconscious party members. Costing 8 SP in battle this spell can be a life saver, but is cumbersome for regular usage due to the high SP usage. Highly recommended for usage outside of battle, doing four times the work of Sacres for 1MP.
Because this spell would have the same effect as Sacres, as well as the simple truth that there are no other allies to heal, this spell cannot be used in ship battles nor cast on the ship from the menu.
Sacrulen is the sixth and final Green spell learned. It summons a brilliant flash of life energy and envelops one ally in a green aurora of healing energy, fully restoring their HP. Oddly, it only costs 6 SP as opposed to Sacrum's 8, but given the utility of sacrum, this is understandable. Sacrulen, and the related Sacrulen crystals become the favored out-of-battle healing method towards the end of the game.
The Noxi chain is responsible for dealing poison damage to the targets. Together with Slipara, Panika and the silver spells (Curia, Risan and the Eterni Chain), the Noxi Chain cannot be cast in ship battles, regardless of the presence of a Magic Cannon. It so happens due to fact that it is impossible to poison a ship.
Noxi is the second Green spell learned. A burst of poisonous gas cast on a single enemy, inflicting damage with a base power rating of 120. It also has a chance of inflicting Poison (if it doesn't kill the target outright). Poison is permanent, and will not dissipate during a battle unless cured, however it is automatically removed at the end of a battle. This spell costs 3 SP per use in battle.
Noxus is the fourth Green spell learned. Summons a powerful burst of toxic gasses that floods the field and strikes the entire enemy party, inflicting damage with a base power rating of 200. It also has a chance of inflicting Poison on all enemies which survive. Poison is permanent and will not dissipate unless cured, however it is automatically removed at the end of battle. Costing 6 SP, this move is a good way to start a long fight.
Below is a table that shows how much Magic Experience each party member needs in order to master every Green spell.
The "Sacri" spell chain is derived from the latin word "Sacrum", meaning holy or sacred. The "Noxi" spells derived from "Noxious", meaning deadly or poisonous.