Instructions
Duel stamps
End three rounds in a draw to get the Cliffhanger stamp. Win one round, and let the computer win the second round. Then do nothing but block in the third round until time runs out.
Get the Straight to the Point stamp by pointing your Wii remote at the screen and lunging it forward to knock your opponent off the platform with a lunge attack.
Obtain the Met Your Match stamp using the same method as in Step 1. Win one round, and let your opponent win the second, then draw in the third round.
Continually block your opponents attacks, and as soon as they are near the edge of the platform hit them once to knock them off and get the One-Hit Wonder stamp.
Play the single-player duel mode and defeat enough opponents until you finally fight against the champion. He will appear after a random number of wins. Defeat him to get the "Last Mii Standing" stamp.
Speed Slice
Win the single-player speed slice mode by beating your opponent on all 10 slices to get the Slice and Dice stamp. To do this, you cannot miss an object.
Keep playing speed slice until you have cut at least one of all 18 different objects to get the Slicing Machine stamp.
Get the Psychic Slice stamp by slicing an object before it hits the ground. The trick is to slice in a random direct after the sensei throws an item and hope you chose correctly. Eventually you will get it correct.
Slice an alarm clock when both numbers on it are the same to get the Double Time stamp.
Continue winning speed slice battles until you compete against the champion. Defeat him and you get the A Cut Above stamp.
Showdown
Complete any stage in the showdown mode without getting hit, and receive the Not a Scratch stamp.
Beat the first 10 stages in the showdown mode to get the Sword Fighter stamp. As the stages progress, you will need to block more and more to defend yourself against the opponents.
Clear Stage 10 without getting hit to get the Perfect 10 stamp. You will need to use a lot of blocking and counterattacks for this one.
Get the Swordmaster stamp by defeating all 70 enemies throughout the 10 levels.
Obtain the "Untouchable" stamp by defeating all 70 enemies in the 10 levels without getting hit. This is possibly the most difficult stamp to obtain, and will require a lot of blocking and patience.