Here is the full list of all 29 forma.8 achievements.
Reactivate your Bomb
Find the first Energy Flower
Find the first artefact
Find the first Secret Object
Reactivate your Shield
Discover the Wrecked Ship
Defeat the Evil forma
Find the lost forma
Find the Futuridium ship
Reach the Dystopian Fortress
Find the depleted Energy Source
Beat the Fire Plant
Kill the Corrupted forma
Escape the energy swarm
Destroy the Guardian Turret
Defeat the Wrecked Titan
Open all passages
Reunite the alien family
Find all Energy Flowers
Reactivate your Turbo
Reactivate your Teleport
Gain the disguise skill
Reactivate the Mini Turbo upgrade
Reactivate the Dual Bomb upgrade
Reactivate the SuperShield upgrade
Reactivate the Enhanced Cooldown upgrade
Find 25 artefacts
Unlock access to the Lost Temple
Return to the Mysterious Island by night