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