The Tier 3 evolution menu was the most complex interface the System had presented to him, which was saying something given that previous menus had included "choose between a spike and a tail" and "do you want to be a sponge, a jellyfish, or a worm." It unfolded in layers, each option branching into sub-options, preview data partially blurred like a road sign approaching at speed.

  [TIER 3 EVOLUTION: COMPLEX MULTICELLULAR ORGANISM]

  [YOU WILL TRANSITION FROM A COLONIAL ORGANISM TO A TRUE MULTICELLULAR BODY PLAN. ORGAN SYSTEMS WILL DEVELOP. SENSORY CAPABILITIES WILL EXPAND SIGNIFICANTLY.]

  [CHOOSE YOUR BODY TYPE:]

  [1. AQUATIC VERTEBRATE (FISH-TYPE)] - Streamlined aquatic body with internal skeleton. Gills, fins, lateral line sensory system. High speed. Opens paths toward: Marine megafauna, Deep-sea organisms, Pelagic apex predators. NOTE: This path remains fully aquatic through Tier 4.

  [2. TERRESTRIAL ARTHROPOD (INSECT/ARACHNID-TYPE)] - Exoskeletal body plan with jointed limbs. Air-breathing through spiracles. Moderate speed, high durability. Opens paths toward: Terrestrial predators, Chimeric fauna, Swarm organisms. NOTE: This path transitions to land biome at Tier 3.]

  [3. AMPHIBIAN BRIDGE (TRANSITIONAL-TYPE)] - Semi-aquatic body plan capable of both water and land operation. Lungs AND gills. Four limbs. Moderate capabilities across all environments. Opens paths toward: Land vertebrates, Mammalian fauna, Equine-type organisms. NOTE: This path transitions to land biome at Tier 4.]

  Andy read the options.

  Then he read them again.

  Then he read the third option a third time, specifically the phrase "equine-type organisms," and felt something click into place with the mechanical precision of a lock accepting the correct key.

  Equine-type organisms. Horses. The amphibian bridge led to land vertebrates led to mammals led to horses. And horses were four-legged creatures with hooves and manes and, in the specific case that was currently occupying ninety percent of Andy's cognitive bandwidth, the potential for a horn on the forehead.

  A horn on a horse was a unicorn.

  His horn. The calcium spike he had chosen as a bacterium because he always picked the pointy option. The horn the System had tracked through three tiers. Six total stages. Two-thirds complete.

  Horn on a cell. Horn on a jellyfish. Horn on a frog. And then horn on a horse.

  "Oh," Andy thought. "Oh no. Oh yes. The System has been building me toward UNICORN since I was a CELL. Since I picked the calcium spike because I always pick the DPS option. The horn goes to six tiers. A horse with a six-tier horn is a unicorn. I'm being unicorned. The System is unicorning me."

  He paused.

  "I, a virgin who died on the way to not be one, am going to become a UNICORN. The single most 'horny' creature in all of fantasy. The mythological animal famously associated with virginity and purity. I couldn't make this up. If there is a god, he is not just laughing, he is making this into a PODCAST."

  The fish was tempting. Internal skeleton, gills, fins, high speed. The sleek build. The performance car. It opened toward marine megafauna, and there was a version of Andy's life where he chose fish and spent the next several tiers being a progressively larger, more dangerous ocean creature.

  But fish stayed aquatic through Tier 4. Two more tiers of water. And the fish path did not lead to horses.

  The arthropod was the immediate gratification pick. Land at Tier 3, right away, exoskeleton, jointed limbs. But its paths (terrestrial predators, chimeric fauna, swarm organisms) did not include "equine-type organisms." No horses, no unicorn, no deal.

  The amphibian bridge.

  The transitional form. Lungs AND gills. Four limbs. Moderate capabilities. Not the best at anything. But it led to mammals, and mammals led to equines, and equines plus six-tier horn chain led to the single most absurd, incredible, impossible destination Andy could imagine.

  "I'm going to reverse-engineer this system into making me a unicorn," he thought, with the calm certainty of a man who has just seen the end of the maze from above and knows which turns to take, "and I'm going to be insufferable about it."

  He selected Amphibian Bridge.

  [AMPHIBIAN BRIDGE (TRANSITIONAL-TYPE): SELECTED]

  [INITIATING TIER 3 EVOLUTION...]

  [WARNING: THIS PROCESS WILL TEMPORARILY DISABLE ALL CURRENT ABILITIES WHILE YOUR ORGANISM RESTRUCTURES. ESTIMATED DURATION: VARIABLE. THIS EVOLUTION INVOLVES SIGNIFICANT BODY PLAN CHANGES INCLUDING ORGAN SYSTEM DEVELOPMENT.]

  [NEW SENSORY SYSTEMS WILL COME ONLINE DURING RESTRUCTURING. SENSORY OVERLOAD POSSIBLE. REMAIN CALM.]

  The narrative has been taken without authorization; if you see it on Amazon, report the incident.

  "Sensory overload possible. Remain calm." Andy's equivalent of a deep breath (a bell contraction that expelled water in a slow, deliberate pulse) did nothing to prepare him for what followed.

  The restructuring was, compared to the Tier 2 evolution, violent.

  Not painful (his nerve net went offline before the worst of it), but violent in the structural sense. A building demolished to its foundations and rebuilt with the same materials in a fundamentally different architecture.

  His consciousness rode the process like a passenger in a car being disassembled and rebuilt around them. His body plan shifted from radial to bilateral. Left and right. Front and back. Top and bottom. For the first time, he was oriented.

  Bones formed. Rigid supports, not a full skeleton (the System informed him mid-restructuring, like a text from a contractor: "partially cartilaginous"), but enough to give his body a shape it could hold. He had a spine. The concepts of "head" and "tail" were new. He'd spent his entire jellyfish existence as a bell with no meaningful front or back.

  Limbs budded. Four of them, pushing outward from his trunk like branches from a sapling, each developing its own musculature and nerve fibers connected to the central nervous system that was undergoing the most dramatic upgrade of his evolutionary career.

  The nerve net had been a bicycle. The central nervous system forming now was a car. Possibly a compact with manual windows, but a car. A brain was coalescing at the front of his body, and as it came online, one region at a time, each activation was like a new channel being tuned in.

  Touch came first. Not the broad pressure awareness of the nerve net, but localized touch. Water against his back registered differently from water against his belly. Sediment beneath his forming limbs had texture, grain, physical reality.

  Then proprioception. He knew where his limbs were. Their exact position, the angle of each joint, the difference between a limb at rest and a limb in motion. He was a body in space, and for the first time, he knew the shape of himself.

  Then something new.

  Something wholly novel. No upgrade to an existing sense. A completely new input that his nascent brain struggled to process because there was no frame of reference.

  Light.

  [VISUAL SYSTEM: ONLINE]

  [PHOTORECEPTIVE ORGANS (BASIC EYES): FUNCTIONAL]

  [NOTE: VISUAL ACUITY IS LOW. COLORS LIMITED. DEPTH PERCEPTION REQUIRES CALIBRATION.]

  Andy saw.

  The word was inadequate. What he experienced was closer to revelation. The impulses resolved into shapes, surfaces, the visible, material reality of a world that had been there the entire time, waiting to be seen.

  It was blurry. His visual acuity was comparable to looking through a Vaseline-smeared window during a rainstorm while squinting, which was still, by approximately infinity percent, better than not seeing at all. The water was something between amber and gold, shot through with particles that caught the light from above and scattered it into slow, drifting constellations. The thermal vents below him glowed with actual, visible light, a deep reddish warmth he'd been living above his entire aquatic life without knowing.

  And his horn.

  Andy looked at his own horn for the first time.

  It was on top of his head. Centered, projecting upward and slightly forward from his newly formed skull, a rigid, pale protrusion that caught the light and refracted it with that blue-white luminescence he had previously known only as an inability to be stealthy. Relative to his new body, it was small. A nub. A bony spike the length of his own forelimb, growing from a base fused to the underlying cartilage.

  He could see it. His horn. The source of approximately thirty percent of his internal monologue's material, sitting on his head like a misplaced party hat made of calcium, glowing gently in the warm water. The sight of it was simultaneously absurd and moving. It was small. It was glowing. It was sticking straight up from his forehead.

  He had never been more grateful that there were no mirrors in the primordial lake.

  He was a horned frog-thing. A proto-amphibian with a spike on its head and four stubby limbs and a body plan that looked, he suspected, like someone had described "salamander" to an artist who had never seen one and also hated them. Nine centimeters long, an enormous upgrade from twelve millimeters but still firmly in the "small enough to be eaten by anything with ambition" category. He had lungs (untested, still underwater). He had gills (doing the actual work). He had a mouth, and at the other end, the other thing, which was the first time in his life that eating and excreting were separate activities, and the efficiency gain was frankly staggering. He also had a butt now. A whole butt. After several lifetimes as organisms that absorbed food through their entire bodies, having a dedicated exit was somehow the most adult thing that had ever happened to him.

  And he had eyes. The worst eyes he had ever had. Also the best, by virtue of being the only ones.

  [TIER 3 EVOLUTION COMPLETE]

  [NEW SPECIES: AMPHIBIAN (TRANSITIONAL, SEMI-AQUATIC)]

  [SIZE: APPROXIMATELY 9CM]

  [BODY PLAN: BILATERAL SYMMETRY. FOUR LIMBS. LUNGS AND GILLS. BASIC VISUAL SYSTEM. ENHANCED TACTILE AND PROPRIOCEPTIVE SENSES.]

  [ABILITIES UPDATED:]

  [ACTIVE HUNTING] - Further enhanced. Visual tracking enabled. Multi-sensory detection. Range: Long.

  [LIMB LOCOMOTION] - Walk, swim, climb, and grasp with four semi-articulated limbs. Moderate speed on land and in water.

  [TOXIC SKIN (PASSIVE)] - Dermal glands secrete mild toxin. Discourages casual predators. Does not affect organisms significantly larger than you.

  [REGENERATION (MINOR)] - Slowly regenerate damaged tissue including lost limb segments. Rate: Slow.

  [CALCIUM SPIKE: RETAINED AND ENHANCED] - Horn relocated to cranial position. Hardened. Integrated with skull structure. Functions as primary melee weapon. Faint luminescence persistent.

  [HORN MORPHOLOGY: ACTIVE. TIER 3 OF 6. TRAIT CHAIN: RARE. GROWING.]

  Tier 3 of 6. Growing. That word was new in the notification. The horn was doing something active, something progressive, and the System wanted him to know it.

  [XP: 0/500]

  [NEXT MILESTONE: TIER 4 EVOLUTION]

  Five hundred. The numbers were always getting bigger. But so was he, and so was his horn, and somewhere at the end of the chain there was something waiting that involved a horse and a horn and the word "mythic" and a dead virgin's sense of cosmic irony.

  He looked up.

  Through the blur and the particles and the warm amber light, he could see the surface. A shimmering boundary between the water he had known and the air he had not, and beyond it, blurred into a golden haze, was the world above.

  He kicked his new legs. Clumsily. Gracelessly. Less "swimming" and more "flailing with purpose," but the purpose was upward, toward the light, toward the surface, toward the thing he was becoming.

  Andy Snodgrass had eyes, and the world was beautiful, and he was going to need a much bigger horn.