Fixed encounter

A Fixed Encounter, also known as spiked tiles when referring to games comprised of sprites, refers to a method of entering a battle. Fixed encounters differ from the basic Random Encounters due to their fixed nature; a fixed encounter starts when a player steps on a certain tile or interacts with a certain object.

Fixed Encounters is the normal method for engaging in a boss fight, and will occasionally be accompanied by dialogue, scripted actions or, in later titles, cutscenes.

There are two common uses for fixed encounters, the first being to enter a surprise battle against bosses or stronger enemies. The second use is to impede the player, or to protect an area such as a Treasure Chest. While fixed encounters are a more common feature in the earlier games, they still have appeared in later games in the series. Fixed encounters cannot be protected against with No Encounters abilities.

Final Fantasy
B1 of the Cavern of Earth is notable for having the entire left side of the entrance covered in spiked tiles against either the Hill Gigas or Lizard encounter, making it a popular place for Level Grinding.

The player must interact with the spirits for the fiends, Lich, Marilith, Kraken and Tiamat, and the arch fiend, Chaos, in order to trigger these events.

Final Fantasy II
Fixed encounters are heavily used in Final Fantasy II, often in the form of numerous Trap Room found in many of the game's dungeons. Trap rooms are rooms comprised of many spiked tiles that the user cannot avoid. Since the player starts in the center of the room, and the tiles all possess a high chance of an encounter, the player must usually endure two battles to exit. Though due to this, they are often used as effective level grinding points.

Final Fantasy IV
In the Lair of the Father, on the path leading to Bahamut, three single Behemoth enemies are fought when the player travels over the single-tile thick bridges, and therefore cannot be avoided.

Also, in the Lunar Subterrane, there are various weapons the player can interact with that trigger difficult boss fights, the most notorious amongst these being Dark Bahamut, who guards the mighty Ragnarok sword for Cecil. There are also various chests in the dungeon that will trigger battles as well.

Final Fantasy V
Many boss fights are fought using fixed encounters. When escaping Karnak Castle, a seemingly normal encounter against a Sergeant and two Cur Nakk enemies ensues, which later reveals itself to be a boss fight against the Iron Claw.

In Drakenvale, a special boss fight involving a Zombie Dragon and a Bone Dragon which attack the Golem in a battle where the object is to save the Golem.

In the last section of the Gil Cave, the player is also forced to fight a Gil Turtle upon reaching the deepest part of the cave (the places where tens of thousands of gil lie on the floor).

In the fourth floor of the Pyramid of Moore, after the Mecha Head zone, the player is forced to fight Sekhmet before proceeding to the next floor.

Final Fantasy VII
The first battle of the game is a fixed encounter between Cloud Strife and two MPs. Should the player decide to charge in the front door of the Shinra HQ, the party must defeat two Grenade Combatants. Also in the Shinra building, the party is attacked by two Mighty Grunts on floor 59 upon approaching the elevator to floor 60.

In the Cave of the Gi, stepping on the giant spider webs that block the path will initiate a battle with a Stinger. The battle against the Materia Keeper in Mt. Nibel is fought by running into the enemy.

The Icicle battles fought inside Gaea's Cliff are fought by running into the area beneath the icicles. Getting knocked back by the wind in the Whirlwind Maze forces the party to defeat a Wind Wing. When on the train that takes the player to North Corel from Mt. Corel during the Huge Materia mission on Disc 2, the player faces an encounter on every carriage they jump on. There are several fixed encounters with Underwater MPs and Submarine Crew in the Underwater Reactor at Junon.

The various battles with Ultimate Weapon on the World Map are fixed encounters when the Highwind moves into it, as with the Ruby Weapon. The same can be said for the Emerald Weapon when hit with the Submarine.

Crisis Core -Final Fantasy VII-
Crisis Core has many fixed encounters over the course of the storyline. Some fixed encounters cause enemies to appear and immediately engage Zack, others cause enemies to appear and wander an area, beginning a battle when approached.

Final Fantasy VIII
The encounters whereupon the player witnesses the UFO? flying across the screen carrying an object are triggered by stepping on a specific area on the World Map, and trigger even with the Enc-None ability equipped, making them fixed encounters. After seeing the UFO four times, the player can find it in another fixed encounter on the plateau above Grandidi Forest, right above the Chocobo Sanctuary. After defeating the UFO? the player can meet PuPu in a fixed encounter by visiting the site where Balamb Garden used to be.

In the Deep Sea Research Center, should the player choose to have Zell open the final door instead of using Steam Pressure, the party will have to fight several fixed encounters against fairly strong enemies on the way to Ultima Weapon.

Final Fantasy IX
Fixed encounters are used in Memoria. When traveling through the linear dungeon, the player will enter in four different fights in fixed positions against each of the Four Fiends. This is reminiscent of how the Four Fiends of the original Final Fantasy are fought as fixed encounters at the end of the four final floors. Pandemonium is also home to three fixed encounters: the first against an Amdusias, the second against an Abadon, and the last against a Shell Dragon.

Several spots in Cleyra are also fixed encounters, when heading down the trunk as well as when saving the civilians, if the player choose the wrong path. Additionally, on the way up to Cleyra, the party can fight Sand Scorpion enemies if they allow the character to sink in quicksand. In Mount Gulug, there are three separate fixed encounters with Red Dragons.

In the Evil Forest, while escaping from the forest, there are two specific points where there are fixed encounters with Plant Spider enemies, and in the Ice Cavern, the enemy Wyerd is a fixed encounter if the player were to step into an icy gust. On the world map, if the player chooses a wrong sinkhole when trying to enter the Desert Palace, the player can constantly fight an Antlion.

During the Festival of the Hunt, all encounters are fixed encounters. In Alexandria, while entering the castle and escaping during Disc 2, the party can fight several Alexandrian Soldiers, as well as a Bandersnatch. In Burmecia, there are three fixed encounters with Mimics, and in Gizamaluke's Grotto, the player can fight three Black Mages in a fixed encounter.

Final Fantasy Legend II
Throughout Ashura's Base, the player can encounter fixed encounter or random encounters inside, such as if the player walks into enemies, talks to them, or they walk into them. They'll engage into a battle with the enemies found in the area.