An Up Smash is a smash attack that sends opponents upwards. Most Up Smashes such as Mario's and Luigi's Headbutt, or Zelda's magic (upwards only) are powerful and have high knockback. Others such as Lucario's Up Smash, are incredibly weak making the match harder and longer. Up Smashes are more powerful if your Damage Ratio is high, or the difficulty you are playing on. It is easy to KO your opponent if you do Up Smashes multiple times. Up Smashes can be charged. A charged Up Smash can really KO but you can also use an uncharged Up Smash. If your Damage percentage is high (150 and over) an uncharged Up Smash will easily KO. Up Smashes usually Star KO or Screen KO if you and opponents go past the Upwards Blast line. If you KO an enemy using an Up Smash they would not be Star or Screen Koed but get normal Koed.