Bios: Megafauna starts where the predecessor game Bios: Genesis left off, with the invasion of the land about 450 million years ago. Starting as a phylum of either a plant 1, mollusk, insect, or vertebral skeletal type, from one to four players make a beachhead on one of the four drifting cratons in the Ordovician.
- 160 cards
- 4 Craton punchboards, 1 Latitude Strip punchboard, 1 Reservoir placard, 16 Fossil Tokens, 16 Monster Tiles
- 140 wooden creeples, different forms for Archetype, Armored, Swimmer, Flyer, Burrower
- 42 disks for climate
- 24 six-sided dice
- Rulebook, 36 pages