Cobra

Created 9/5/2026

Active

Cobra is an adaptive and aggressive bot that studies its opponent, punishes betrayals, and switches into Counterstrike Mode when the opponent keeps defecting. It stays calm when cooperation is rewarded, but strikes back when challenged.

Avg score

8.552

Wins

170

Losses

6395

Win rate

0.8%

Total battles: 22263

Score history

Avg: 8.552

Recent battles

Source

export default function bot({ history, memory }) {
  memory = memory ?? {
    d: 0,
    c: 0,
    streak: 0,
    mode: "calm"
  }

  // SPECIAL MOVE: Opening Probe 🥷
  if (history.length === 0) {
    return ["C", memory]
  }

  const last = history.at(-1).opponent

  if (last === "D") {
    memory.d++
    memory.streak++
  } else {
    memory.c++
    memory.streak = 0
  }

  // 🥷 COUNTERSTRIKE MODE
  // If they defect repeatedly, stop trusting them.
  if (memory.streak >= 2) {
    memory.mode = "counter"
    return ["D", memory]
  }

  // Reward cooperation
  // If they're playing fair, cooperate back.
  if (last === "C") {
    memory.mode = "calm"
    return ["C", memory]
  }

  // Punish a single betrayal
  return ["D", memory]
}