https://blockly.games/pond-duck

Blockly Pond

function defensive() {
  function initialState() {
    return {
      toEscape: 25,
      escaping: false,
      health: health()
    };
  }
  
  const Duck = {
    state: initialState(),
    getSafeDirection() {
      const buffer = 30;
      if (getX() <= buffer) {
        return Math.random() * 180 - 90;
      } else if (getX() >= 100 - buffer) {
        return Math.random() * 180 + 90;
      } else if (getY() <= buffer) {
        return Math.random() * 180;
      } else if (getY() >= 100 - buffer) {
        return Math.random() * 180 + 180;
      }
      return Math.random();
    },
    escape() {
      this.state.escaping = true;
      this.state.toEscape--;
      swim(this.getSafeDirection(), 80);
    },
    tick() {
      if (health() < this.state.health) {
        if (!this.state.escaping) {
          this.escape();
        } else if (this.state.toEscape-- < 0) {
          this.state = initialState();
        }
      }
    }
  };
  
  return Duck;
}

function offensive() {
  const initialPrecision = 15;
  var precision = initialPrecision;
  var scanLimit = 30;
  var scanRange = [0, scanLimit];
  
  function detectEnemy(precision, range) {
    let enemyFound = false;
    let enemyDistance = Infinity;
    var direction = range[0];
    while (direction < range[1] && !enemyFound) {
      direction += precision;
      enemyDistance = scan(direction, precision);
      if (enemyDistance < Infinity) {
        enemyFound = true;
        break;
      }
    }
    return {
      enemyFound,
      enemyDirection: direction,
      enemyDistance
    };
  }
  
  function around(number1, number2, proximity) {
    return Math.abs(number1 - number2) < proximity;
  }
  
  function tick({ wait }) {
    if (wait) {
      return;
    }
    let { enemyFound, enemyDirection, enemyDistance } = detectEnemy(precision, scanRange);
    if (enemyFound) {
      if (enemyDistance > 70) {
        swim(enemyDirection, 100);
      } else if ( around(getY(), 50, 5) ) {
        swim(90, 50);
      } else {
        stop();
        cannon(enemyDirection, enemyDistance);
        precision = Math.max(1, precision / 3);
      }
      scanRange = [ enemyDirection - scanLimit, enemyDirection ];
    } else {
      precision = initialPrecision;
      scanRange = [ scanRange[0] + scanLimit, scanRange[1] + scanLimit ];
    }
    if (scanRange[0] >= 720) {
      scanRange = [0, scanLimit];
      swim(Math.random() * 360);
    }
  }
  
  return {
    tick
  };
}

const defense = defensive();
const offense = offensive();

while (true) {
  defense.tick();
  offense.tick({ wait: defense.state.escaping });
}