Here is the full list of all 44 Shadow Tactics: Blades of the Shogun - there are Aiko's Choice achievements.
Find all hidden caves in Hana Gakuen.
Kill Lady Chiyo without getting a disguise.
Kill Lady Chiyo with any character other than Aiko.
Talk to a samurai when disguised with Aiko.
Kill or knock out 5 guards at the same time with all 5 characters.
Don't kill anyone with Takuma during the mission “The Best Laid Plans.”
Collect 17 badges.
Come out of the other side of the river in Nagoya.
Listen to everything Kuma has to say.
Finish all missions.
Finish “The Secrets of Hana Gakuen”.
Kill 10 guards with Takuma's Sniper Rifle that are farther than 25 meters away from him.
Use Aiko's disguise 15 times.
Execute a plan with all 5 characters.
Kill 30 guards with the help of the environment.
Kill 10 guards with traps in Hana Gakuen.
Hide with all characters in a single bush.
Fail the Shrine riddle at the beginning 3 times.
Finish the mission “Red Lights at Matsuyama”.
Don't extinguish any light sources in Matsuyama.
Finish the mission “The Best Laid Plans”.
Kill the Captain.
Travel 1200 meters in water during the mission “The Best Laid Plans”.
Kill 3 Samurai with Yuki.
Hide 150 bodies.
Find the perfect spot for sunbathing.
Kill or knock out 150 guards.
Finish the mission “A Night at Sea”
Kill at least 3 guards in the mission “A Night at Sea”.
Distract 4 guards at the same time with Kuma.
Finish the mission “Reunion at Nagoya”.
Kill all enemies at the mansion in Nagoya.
Hide 100 bodies.
Distract 50 guards with Hayato's stone.
Kill 10 guards with a drop attack.
Kill or knock out 100 guards.
Kill a Samurai with a flower pot.
Kill a samurai with a rock.
Hide 50 bodies.
Kill 20 guards with Mugen's Swordwind.
Kill or knock out 50 guards.
Kill a guard with a drop attack from a rope.
3 times in one mission, kill 2 guards at once with Mugen's Swordwind.
Throw a guard into a well.