Collect 100 score balls (coins) without dying
Collect the hidden 1-up from level 1-1 (hint in achievement icon).
Collect the arm blaster powerup (fire flower)
Complete level 1-1 without going (or turning) left in one life. Standing still is allowed.
Complete level 1-3 without going (or turning) left in one life. Standing still is allowed.
Clear world 1 and defeat Dr.Wily! (Continues allowed)
Clear world 2 and defeat Dr.Wily! (Continues allowed)
Clear world 3 and defeat Dr.Wily! (Continues allowed)
Clear world 4 and defeat Dr.Wily! (Continues allowed)
Clear world 5 and defeat Dr.Wily! (Continues allowed)
Clear world 6 and defeat Dr.Wily! (Continues allowed)
Clear world 7 and defeat Dr.Wily! (Continues allowed)
Clear world 8 and defeat Dr.Wily once and for all! (Continues allowed)
Clear the harder world 1 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 2 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 3 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 4 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 5 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 6 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 7 and defeat Dr.Wily! (Continues allowed)
Clear the harder world 8 and defeat Dr.Wily once and for all! (Continues allowed)
Complete hard mode with no deaths, warps allowed
Complete the standard game with no deaths (warps allowed).
Reach the warp zone of 1-2.
Reach the warp zone of 4-2.
Reach the super secret warp zone of 4-2.
Complete level 4-1 without moving left in a single life. (No continues or warps allowed)