JSFiddle - React, Tailwind, and code Playground

HTML

<div id="text">
**** long ********* ****
</div>

JavaScript

function play(encText, decrText) {
      function showText() {
        var text = decrText.substring(0, i + 1) + encText.substring(i + 1);
        console.log(text);
        document.getElementById('text').innerHTML = text;
      }

      for (var i = 0; i < encText.length + 1; i++) {
        setTimeout(showText(), i * 5000);
      }

    }

play(document.getElementById('text').innerHTML, 'some long encrypted text')