In Undertale, the game mechanics concerning HP (Health Points) follow a structure that aligns with traditional RPG standards, where a player faces a game over if their HP is reduced to zero. This pivotal mechanic serves as a fundamental aspect of the game’s challenge and overall design, emphasizing the importance of battles and the consequences of failure.

Game Over Mechanics:
– Standard Outcome: When your character’s HP reaches zero during a combat encounter, a “Game Over” screen appears, indicating that your character has been defeated. This prompts players to either continue from their last save point or quit the game, reflecting a loss in the current fight.[4]

Unique Exceptions:
– Scripted Fights: Undertale introduces notable exceptions to the conventional mechanics in specific scripted encounters. For instance, during the fight with Papyrus, players may have their HP reduced to 1, but instead of encountering a typical game over, the fight advances to the next sequence. This deviation emphasizes narrative progression over strict adherence to gameplay rules, allowing for story-driven moments that differ from standard battle mechanics.[1]

Character Mechanics:
– Sans’ Battle: Certain characters, such as Sans, showcase unique battle mechanics. While his attacks deal minimal damage, they can bypass normal invincibility frames, maintaining a high level of challenge for the player. Even in these cases, however, the fundamental rule remains intact: a player’s HP dropping to zero signifies defeat, culminating in a loss for the battle.[5]

Summary:
In summary, the core gameplay in Undertale adheres to the principle that reaching zero HP results in a game over, necessitating a restart or reload from the last save. However, the game creatively incorporates exceptions in key encounters that enhance narrative engagement, enriching the player’s experience and distinguishing Undertale from typical RPGs while still upholding the overall context of health and defeat in combat scenarios.[4][2]