Strategy Duel
Compare two strategies directly over many rounds.
Repeated Prisoner's Dilemma Tournament
Rounds0
A score0
B score0
Cooperation rate0%
How this teaches game theory
Complete scenario, mode, and level guide
Repeated interaction changes incentives because today's move influences how opponents behave tomorrow.
Round-Robin Tournament
Every strategy plays every other strategy; total payoff determines the leaderboard.
Evolutionary Tournament
Scores are converted into population shares, linking repeated games to evolutionary selection.
Strategies
Always Cooperate / Always Defect
Useful baselines that expose exploitation and the short-run temptation to defect.
Tit-for-Tat
Starts cooperative, then copies the opponent's previous move. It combines reciprocity and immediate forgiveness.
Grim Trigger
Cooperates until the opponent defects once, then defects forever.
Generous Tit-for-Tat
Usually reciprocates defection but occasionally forgives, making it more robust to noise.
Win-Stay, Lose-Shift
Repeats a move after a good outcome and switches after a poor one.
Levels
Level 1 — 20 Rounds
Short horizon for quickly understanding strategy logic.
Level 2 — 100 Rounds
Longer interaction makes reputation and retaliation more consequential.
Level 3 — Noise
One hundred rounds with accidental move flips, testing forgiveness and robustness.
What to observe: no strategy is universally best. Performance depends on the population of opponents, the horizon, and whether mistakes occur.