Here is the full list of all 13 Avalon achievements.
You learned how to play Senet.
You met a Super Villain!
You got to see some of Penny's backstory.
You got to spend time with Maize!
The secret unlock code is megalodong.
Finished the Bonus Act.
Finished Act Seven.
Finshed Act Six.
Finished Act Five.
Finished Act Four.
Finished Act Three.
Finished Act Two.
Finished Act One.