I’ve played #Metazooa hundreds of times and I think I’ve cracked the optimal path.

Note when the game offers an uncommon taxon; it’s trying to “make room” for a specific species that doesn’t fit into a more common taxon.

Most common openers:

Always guess “box turtle” first. If the parent is Amniota you likely have a mammal; guess a placental one. Preferably a domestic one because they have a lot of taxa above them. Guess one domestic hooved mammal (I like cattle), and if that doesn’t narrow it down to Artiodactyla or something more specific then switch to a different member of Laurasiatheria. If you’re somehow at Boreoeutheria, guess a rodent with many taxa above it like a chipmunk.

If the parent of your first guess is Archelosauria, you likely have a bird; robin and goose are good guesses. If you guess one and the parent is Neognathae, guess the other. If it’s something more specific, guess a closer relative. This’ll narrow down the order of birds quickly.

If after guessing “box turtle” you find that the parent is Bilateria, switch to symmetrical invertebrates (not starfish unless it’s a more specific parent). If it’s something more specific that includes fish but excludes invertebrates, guess a fish. Don’t start with sharks; they’re too isolated from the other fish with more taxa above them.