Research Report: Experience Points and Stat Leveling Systems - wwestlake/Labyrinth GitHub Wiki

Research Report: Experience Points and Stat Leveling Systems

1. Experience Points (XP) Calculation for Leveling Up

Common Methods to Calculate XP Required for Leveling Up:

  1. Linear Progression:

    • Formula: XP for Next Level = Base XP * Level
    • Description: The XP required increases linearly as the character levels up. This is the simplest method, where each level requires a fixed amount of additional XP compared to the previous level. It’s often seen in early or simple RPGs.
    • Pros: Easy to implement and understand.
    • Cons: Can become boring over time as it doesn’t adequately reflect the increasing difficulty of progressing.

  2. Exponential Progression:

    • Formula: XP for Next Level = Base XP * (Level ^ Exponent)
    • Description: This method increases the required XP exponentially as levels increase. Common exponents used are 1.5, 1.8, or 2.0. It creates a steep curve, making higher levels significantly harder to achieve.
    • Pros: Better reflects the increasing difficulty of progressing through higher levels.
    • Cons: Can become too difficult if not carefully balanced.

  3. Logarithmic Progression:

    • Formula: XP for Next Level = Base XP * log(Level + Constant)
    • Description: Logarithmic progression slows the increase in required XP over time. It's useful for games where leveling up should remain attainable even at higher levels.
    • Pros: Provides a more gradual difficulty curve, which can be appealing for long-term engagement.
    • Cons: Can make earlier levels feel too easy if not balanced properly.

  4. Hybrid Models:

    • Description: Many games use a combination of the above methods. For example, early levels might use linear progression, transitioning to exponential at mid-levels, and then logarithmic for high levels.
    • Pros: Balances difficulty and player satisfaction across different stages of the game.
    • Cons: More complex to implement and balance.

Resetting XP After Level-Up:

In games where XP resets after each level-up, the XP required for each level is generally calculated independently of the total XP accrued by the player. The XP counter resets to zero upon leveling up, and the player starts earning XP toward the next level. This approach is common in many RPGs because it provides a clear and consistent reward cycle.

Exponential Growth Example:

  • Level 1: 1,000 XP
  • Level 2: 2,000 XP (exponential growth factor of 2)
  • Level 3: 4,000 XP
  • Level 4: 8,000 XP
  • Level 5: 16,000 XP

The exponential growth ensures that each subsequent level is significantly harder to achieve, which can keep the game challenging and rewarding over time.