Retro sci-fi pulp style, cosmic horror, a monstrous robotic entity emerges from an interdimensional portal, surrounded by the remnants of fallen civilizations and otherworldly phenomena, tentacle-like cables, reality-warping effects, eldritch symbols, a chaotic scene with a swirling energy vortex, a cosmic void with floating debris, a vibrant alien sun backlighting, eerie color shifts, and a bold contrasting color palette.