The Mutated Heart is a grotesque, organic item with a pulsating, irregular shape, resembling a human heart but enlarged and twisted with unnatural growths. Its surface is covered in veiny, dark red and purple tissues, with patches of glossy, slime-covered areas and pulsating luminescent veins that emit a faint, eerie glow. The heart is encased in a semi-transparent, membrane-like sac that occasionally twitches, suggesting it's still alive. Distinctive features include protruding, bone-like spikes and occasional, involuntary contractions that make it seem as though it's struggling to beat.