JSFiddle - React, Tailwind, and code Playground

HTML

<div class="character">
    <img src="http://img194.imageshack.us/img194/3854/goldgladiator.png">
    <div class="green-mask"></div>
</div>

CSS

.green-mask {
    display: block;
    height: 200px;
    width: 508px;
    background: rgb(160, 255, 97);
    opacity: .3;
    position: absolute;
    top: 0;
    -webkit-mask-image: url(http://img194.imageshack.us/img194/3854/goldgladiator.png);
}