Here is the full list of all 40 Bold Blade achievements.
Win the game, by completing all areas
Complete area 1
Complete area 2
Complete area 3
Complete area 4
Complete area 5
Complete area 6
Complete area 7
Complete area 8
Complete area 9
Complete area 10
Reach a high score of 1000 in Bug Boshers
Reach a high score of 6000 in Bug Boshers
Reach a high score of 12000 in Bug Boshers
Upgrade length to 50
Upgrade width to 50
Upgrade your strength to 10 at the Shrine of Korim the Mighty
Upgrade your vitality to 10 at the Shrine of Olbon of the Deep Earth
Upgrade your stamina to 10 at the Shrine of Meridys the River Empress
Upgrade your mind to 10 at the Shrine of Xorduntanth the Voiceless
Complete area 1-1
Complete area 1-2
Complete area 2-1
Complete area 2-2
Complete area 3-1
Complete area 3-2
Complete area 4-1
Complete area 4-2
Complete area 5-1
Complete area 5-2
Complete area 6-1
Complete area 6-2
Complete area 7-1
Complete area 7-2
Complete area 8-1
Complete area 8-2
Complete area 9-1
Complete area 9-2
Complete area 10-1
Complete area 10-2