The Animal Index is the collection ledger. The official place text tells you to complete it for special rewards and calls out rare sizes, Mythics, and Secret animals. It does not publish the reward table or the odds.
What to do with it
Open the Index on day one so a new hatch is obvious. After any session that discovers something, reopen the Index and claim whatever the UI offers before you leave the plot. Unclaimed rewards are delayed power. Players who ignore the Index for a week often overlook a creature that would have completed an entry.
Progress still comes from the egg loop: speed, a ride sized to free slots, placement, hatching, then a look at new ticks. The Index scores that work. A full plot with no free slot is an inventory lock, not bad luck.
What the labels mean here
- Mythic and Secret are official rarity names. Treat them as long-term finds. Keep the rest of the plot earning while you hunt.
- Rare sizes are a separate axis when the Index shows them apart from the base creature. Do not assume every large or tiny hatch counts until the Index says so.
- Common and Rare are community shorthand for early and mid finds. They are not spelled out as a ladder on the place page. Use them only as the labels your client actually shows.
No percentage, pity counter, or zone-exclusive table is published in the sources used here. High hatch volume and more than one reachable route are the honest method.
Which gap to chase
- Easy entries your current nearby routes can finish.
- Gaps that match the route you already clear reliably.
- Higher rarities after speed and capacity can support a longer session.
- Secret or Mythic hunts as a stretch goal, not as the only plan.
A speed upgrade that opens three new entries can beat forcing one stubborn gap on a weak route. Once income is stable, an Index gap can matter more than a third copy of an animal you already logged. An empty slot is still worse than a Common that is earning.