Area or location where the player can practice moves on a more or less unbeatable character. The usual experience isn't given, although a character may earn information or special items. You can't win the fight, and you can lose.
If the player is forced to fight them at least twice, the character will get more difficult with each fight. Thus, it may become a Recurring Boss.
Contrast with the Training Dummy, which is an opponent that you can't lose against.
- The City of Heroes tutorial zone "Outbreak" includes a parking lot at an abandoned motel where the police have set up unkillable Rikti drones for new heroes to practice their attacks on.
- The City of Villains tutorial "Breakout" similarly has deactivated police drones. And much later, the co-op Vanguard Base has Rikti-shaped training dummies.
- In Monster Rancher EVO, Baron Dotty is a training boss with a twist: You can't lose to him. In addition, he's a Recurring Boss, but always rather hard to lose to every time. His theme song and fight song are cool, though.
- Your superiors, Girardot and Abelia, from the early chapters of SoulCalibur III's Chronicles of the Sword mode. They challenge you to test your worthiness in battle at first, but when you face off against them later on: it's for keeps.
- Master Tetsu in Legend of Legaia. Near the end of the game, he becomes a Bonus Boss.
- Chrono Trigger has two of these. The first one is Gato at the Millenial Fair, who can be fought for Silver Points to spend at the fair. The second is Spekkio, found at the End of Time, who gives the player characters the ability to cast magic. Spekkio gains a new form every ten levels or so you gain, and the first time the player beats him in any given form, they're given a prize pack, each one including at least a few tabs that permanently raise their stats. He also keeps gaining levels across every New Game+.
- Radius in Chrono Cross. Amusingly, if you fight him on New Game+ and survive his attacks, he'll praise you for how strong you are.
- Orca from The Legend of Zelda: The Wind Waker. Later in the game, you can win a prize if you spend a ridiculously long amount of time whaling on him.
- The Komamen from Jump! Ultimate Stars.
- Mother 3 has a function in the Battle Memory that lets you practice Combos against an unresponsive version of any enemy you've encountered.
- In an interesting take, Vagrant Story actually gives you dummies to practice on, which you find in various places. This is useful even late-game because as you attack the dummy, your skill against that particular enemy type (say, lizards) will increase even though the dummy never moves and is practically indestructible.
- Call of Duty 2 actually justifies this - immediately after basic training, the player must destroy a German armored car that enters the area.
- Tales of Vesperia has Adecor and Boccos, a pair of knights who are after Yuri for his miscellaneous crimes. They appear and challenge you several times throughout the first part of the game, and serve to teach the player about various combat techniques such as Overlimit and Burst Artes.
- Averted in Demon's Souls Its first boss is beatable, but it can and will one hit KO you. If you survive that one, there is a second, bonus boss, waiting for you. One that cannot be damaged. Don't worry though, after you take a level in badass, you get to kill both of them later!
- Before the real fight against him, Augus from Asura's Wrath is this for the Tutorial Level in episode 3. You don't have to fight him and both he and the tutorial segments before him can be skipped, but doing so counts against your level rating.
- The first fight against a Big Sister in BioShock 2. She's programmed to jump onto the giant window, slice it apart, and then swim away before you can beat her.
- To a lesser extent, the first spider splicer you fight in BioShock. As Wilkins points out after scaring her off with a security bot, "That one's too tough for you!" The idea is that you can only beat her once you've gotten the requisite upgrades by researching the spider splicers in the level, she can't be killed at first but in a second encounter you'll be able to finish her, at that point she's almost as tough as a big daddy but no more dangerous than any other spider splicer.
- Two Goombas in Mario & Luigi: Superstar Saga.
- Megaman Sprite Game contains an in-universe example of this trope. The Yellow Devil is training to become a final boss, so he asks you to fight him for practice.
- Dante serves this role in the beginning of Devil May Cry 4, where Nero demonstrates his most basic moves on him. Afterwards, he decides to play along with you and becomes a proper Warm-Up Boss.
- In the beginning of Jade Cocoon you can face Korus in a training battle that pits you against his Arpatron to explain the combat and capture system, and you get to keep his monster for your trouble. This is your only chance in the entire game (not conting the non-canon Eternal Corridor) to capture one of these things, though you can capture up to 12 from him by exploiting a glitch.