Here is the full list of all 39 Bandle Tale: A League of Legends Story achievements.
Fully upgrade the Leg
Host the final party at the Unity Tree
Arrange a date for Rumble and Tristana
Reunite Yarnville with Bandle City
Gather Champions Council at the headquarters
Fail to host a Food Stand
Fully upgrade your house
Rescue Clover
Host a Beachgoers' Bash on Inspiration Isle
Find Veigar on the beach
Visit all lookout points in Bandle City
Host a Dance Battle Bash in Gadgeton
Host a Big Bug Social in Greensprout Grove
Host the Awesome Yordle Fest
Host an Open Air Concert on Inspiration Isle
Talk to Teemo for the first time
Host a Harvest Festival in Greensprout Grove
Fail to throw a Festival
Host an Inventors' Fair in Gadgeton
Sell 50 items through a vending machine
Catch 50 items from the portal
Serve food to 20 guests
Talk to Rumble for the first time
Talk to Lulu for the first time
Try portal fishing
Hold your first lecture at Bandle University
Sell your first item through a vending machine
Upgrade your house for the first time
Throw your first Festival
Make your home portable
Throw your first Food Stand
Plant your first seed
Collect 50 resources from objects
Talk to Corki for the first time
Talk to Tristana for the first time
Talk to Veigar for the first time
Sleep for the first time
Leave Gramps's house for the first time
Knit your first yarn