exports.run = function(client, message, args){
   if (args.length < 1) { args = 6; }
   
   var x = args;
   var y = Math.floor(Math.random() * (Math.floor(x) - Math.ceil(1) + 1)) + Math.ceil(1);

   message.channel.send(`🎲 You rolled a ${y}! 🎲`);
};

exports.conf = {
  enabled: true,
  guildOnly: false,
  aliases: ["roll"],
  permLevel: 0
};

exports.help = {
  name: "Roll",
  description: "Roll a die.",
  usage: "roll <sides>"
};

exports.run = function(client, message, args){
   if (args.length < 1) { args = 6; }
   
   let x = args;
   let y = Math.floor(Math.random() * (Math.floor(x) - Math.ceil(1) + 1)) + Math.ceil(1);

   message.channel.send(`🎲 You rolled a ${y}! 🎲`);
};

exports.conf = {
  enabled: true,
  guildOnly: false,
  aliases: ["roll"],
  permLevel: 0
};

exports.help = {
  name: "Roll",
  description: "Roll a die.",
  usage: "roll <sides>"
};

Update roll.js