Combat happens on rectangular battlefields (maps), which are somewhat reminiscent of chess boards, as they are comprised of tiles. At the beginning of each battle, you are allowed to pick five characters (units) from your team. Ramza is mandatory for storyline battles, but not for random ones. Similarly, guest characters participate in storyline battles, but not in random ones. You can also choose your units’ starting positions on the map (within a certain area). The placement also depends on the side you enter the area from on the World Map. This is mostly useful once you know the layout of a given map, so that you can plan out your approach. For some storyline battles, you will also need to form your five units into two squads.
Turn order is determined by a unit’s speed, and when their turn comes up, they can do two things: Move and Act. Movement range depends on the unit’s job: they can move a certain number of tiles horizontally (their “Move” stat) and a certain number of tiles vertically (their “Jump” stat). The map can have a variety of terrain to render this more difficult, such as mountains, ravines, rivers/lakes, swamps (which poison a unit that stands in them) or, on one map, lava. Most monsters can’t enter water, and while human units can, their movement range will be halved if the depth is one tile (this also happens in swamps, but only when it rains). If the depth is two tiles, they won’t be able to Act.
Acting is pretty straightforward: you pick an ability from either of the characters’ Action Abilities, and it will be executed after a certain number of turns, indicated by its Charge Time (CT). Each character also has a CT gauge on their combat menu, indicating how quickly their next turn will come (alternatively, you can check the turn order by pressing Triangle), so be smart and don’t pick an ability with a long CT if you know that your target’s turn is up next, because they can and most likely will move out of range. Abilities can be targeted on a character or on an area (if they are multi-target), which allows for some preemptive thinking. You can also choose to Wait, either instead of doing anything, or Move, then Wait, or Act and don’t Move. This will make your character’s next turn come quicker. Guest characters are A.I. controlled in combat, so you don’t have any input on what they do, but you can change their equipment, their abilities and even their jobs in-between battles.
As mentioned previously, each character can have two Action Abilities (one from its own job and one from any other one), one Reaction Ability, one Support Ability and one Movement Ability. Reaction Abilities will trigger upon certain conditions being met (like getting hit or losing HP), Support Abilities are always active and Movement Abilities trigger every time a character moves. Most Action abilities have success rates, which are indicated as percentages on the battle menu. Although, let me be clear: the game cheats, as the RNG is biased against you. Don’t be surprised to see an enemy unit land an attack with a 20% success rate, only to see one of your own units whiff a 90% chance right afterwards. It’s annoying, but there you have it. Success rates depend on many things: sometimes it’s a character’s speed, sometimes their Brave(ry) or their Faith, and sometimes their Zodiac sign.
Brave(ry) and Faith are two very important stats. The former indicates the success rate of a character’s Reaction Abilities and influences attack power with certain kinds of weapons. So, in short, it’s always beneficial to have high Brave(ry). With one notable exception: Move-Find Item/Treasure Hunter. Some map tiles contain treasure–either a good item or a Phoenix Down–and the lower the character’s Brave(ry), the higher the odds of getting the good item. And you only have one chance at each: if you get the Phoenix Down, the good item will be gone forever. So keeping one character with low Brave(ry) (looking at you, Rafa/Rapha) for treasure hunting purposes is a good idea, even though you’ll mostly find the really worthwhile stuff in the Deep Dungeon/Midlight’s Deep. Keep in mind that enemy units can also pick up these items, so if there’s something you really want, you need to make sure that it won’t get swiped from under your nose. Be careful, however: if a character’s Brave(ry) drops below 3, they will leave the team because they have become too cowardly (they will warn you before it gets to that, though). Although it seems to me that you actually have to actively work to make that happen. Besides, a character with a Brave(ry) lower than 10 will turn into a chicken in combat anyway. Another thing worth noting is that some tiles also contain traps (usually the same tiles that contain treasure), which have a higher chance of triggering if a character with high Brave(ry) and without Move-Find Item/Treasure Hunter moves onto them. Although, if that happens, someone with Move-Find Item/Treasure Hunter can still pick the treasure up afterwards. Or you can simply send them in to pick up the item without triggering the trap in the first place.
Faith indicates the potency of magic, either beneficial or offensive, so it’s a double-edged sword. On the one hand, a character with high Faith will deal more magic damage and recover more HP from curative spells, as well as having better odds of Raise working on them if they die. But, on the other hand, they will also take more damage from offensive magic spells. Low Faith is also problematic if you need to cure or Raise the character in question (c.f. Malak/Marach). So you need to keep a happy balance for physical units, but pump up the Faith for magic ones. Just be careful not to go above 97, or the character will leave to become a religious hermit. Again, though, they will warn you before that happens. This does not apply to the Pray Faith/Belief spell, however: that only maxes out a character’s Faith for the duration of the battle.
As you may have noticed, each character also has a Zodiac sign. While you can’t do much about the signs of unique characters, you can pick Ramza’s sign and choose generic units to recruit by sign. Signs have compatibility patterns which affect damage, healing and the success rate of any abilities which don’t have a fixed one (e.g. Raise or Talk Skill/Speechcraft). To wit: best compatibility applies a 1.5 multiplier to the variable in question, while worst compatibility applies a 0.5 one. Good compatibility applies a 1.25 multiplier, while bad compatibility applies a 0.75 one. The best way of visualising this is drawing all the signs in a circle. If you draw an equilateral triangle starting from a given sign, the two other points of the triangle have good compatibility with said sign. If you draw a square starting from a given sign, the two nearest points to it have bad compatibility with said sign, while the point directly opposite hast best/worst compatibility. Whether it’s best or worst depends on the unit’s gender: best compatibility with a unit of the opposite gender and worst with a unit of the same gender. You can safely go through the game ignoring this entirely, but it can add an extra layer of strategy if you’re so inclined. As for monsters, since they don’t have a gender, if they happen to be a sign which would entail best/worst compatibility with a unit, it’s just considered as bad compatibility instead.
As I have mentioned previously, one annoying aspect of the combat system is that anybody can die. Whenever a unit goes down, they fall to the ground unconscious, and a countdown starts from 3, based on that unit’s CT gauge. Once that countdown reaches 0, the unit will be gone forever on the next turn (unless they’re undead, in which case, there’s a 50% chance that they’ll revive), leaving behind either a treasure chest with an item or piece of equipment inside, or a crystal which will either replenish the HP and MP of any unit (friendly or hostile) that picks it up, or teach them one of the character’s abilities. This means that you can sometimes learn abilities from fallen enemies, but it also means that you have to be very careful with your own units. Another consequence of this is that they essentially forfeit any character development once they join the party, which is a damn shame. But, to be fair, it does also add an edge of urgency to combat.
Units earn EXP and JP from taking actions in combat, so it helps if your characters can always do something, even if they can’t attack a target right away. Attacks from the side or from behind have a higher chance of success and will deal more damage, but there are no such things as preeemptive or surprise attacks per se.
There are seven types of magic in the game (black, white, yin-yang/mystic, time, speechcraft, summoning and geomancy), and spells are learned with JP like any other ability. There are, however, some exceptions: the –ja spells, some summons and Ultima. Ultima can only be learned by Ramza (and Luso in WotL) if he survives it. Similarly, Zodiac/Zodiark can only be learned by a Summoner surviving it, but it’s only a 90% chance. This can also happen with the –ja spells, Lich, Cyclops, Salamander, Odin, Leviathan and Bahamut. However, the chances here range from 10 to 40%, and mages that know these spells don’t exactly roam the streets. So just count yourself lucky if one of your characters happens to learn them this way, as it’ll save them some JP grinding.
Weather has an effect on the potency of some spells: lightning spells will notably be stronger in a thunderstorm, while fire spells will be weakened when it rains. Ice spells will be more effective in snowy areas. Additionally, rain and night-time will lower the accuracy of projectile attacks.