Here is the full list of all 18 Karate Master 2 Knock Down Blow achievements.
Defeat Oboro.
Defeat the bear.
You need to earn 1500 bucks.
Requires KI 10
Requires toughness 10
Requires speed 10
Requires tai kitae 10
Win the Kumite tournament.
Defeat the legendary Sensei Matsu.
Reach fame 100.
Jump over a car.
Win a Karate-Pro tournament.
Requires strength 10
Win a ring event.
Defeat the bull.
Win a Full Contact Karate tournament.
Win a Bogu Kumite Tournament.
Heal yourself in the hospital.