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