emoji-theft.js

const { Client } = require('discord.js');

const Discord = new Client();

const commands = {
  steal: (emoji, name, message) => {
    const emojiId = emoji.match(/([0-9]+)/)[0];
    if (!emojiId) return message.reply('Emoji ID not found');

    message.guild.createEmoji(`https://cdn.discordapp.com/emojis/${emojiId}`, name)
      .then((newEmoji) => {
        message.react(newEmoji);
      })
      .catch((err) => {
        console.error(err);
        message.react('👎');
      })
  }
}

Discord.on('message', (message) => {
  if (!message.content.startsWith(':')) return;
  const content = message.content.substring(1);
  const [command, ...args] = content.split(' ');
  
  if (command in commands) commands[command](...args, message);
  else message.reply('Command not found');
})

Discord.on('ready', () => {
  console.log(`Logged in as ${Discord.user.username}`);
})

Discord.login('BOT_TOKEN');