<?php

$weapons = ['fists', 'whip', 'gun'];
$opponentWeapon = $weapons[rand(0,2)];
$indyWeapon='???';
if ($opponentWeapon==$weapons[0]) {
    $indyWeapon = $weapons[2];
    echo $indyWeapon;
} elseif ($opponentWeapon==$weapons[1]) {
    $indyWeapon = $weapons[0];
    echo $indyWeapon;
} else {
    $indyWeapon = $weapons[1];
    echo $indyWeapon;
}