Invincibility frames are the period of time (measured in frames) during which a character cannot be damaged. Depending on which kind of invincibility the character has, the attack may "hit" or "miss".
A character with invincibility will be hit by attacks (so the attacker takes hitlag), but will not take damage or hitstun. This can be thought of as "blocking invincibility". For example, characters using a Starman have invincibility, as well as characters about to throw someone (this invincibility lasts 8 frames). Other examples of invincibility include:
- The 5 seconds (300 frames) before dismounting a revival platform.
- The 2 seconds (120 frames) after dismounting a revival platform.
- The secondary Ice Climber for a second (60 frames) when Belay is used.
- The start of Lucas' and Ness' PK Thunder 2.
- The entire duration of Squirtle's Withdraw
- Ike's Counter only 1 frame
A character with intangibility will not be hit by attacks. For example, a projectile will travel right through him or her. Intangibility is often attributed to dodges, techs, edge-grabbing, get-up attacks and animations, and certain body parts during certain moves. Since the character is not hit, a long-lasting attack (or very short intangibility time) may still hit the character once it ends. Intangibility can also be called "dodging invincibility".
- Marth's Counter Only 1 frame.
- Roy's Counter Only 1 frame.
- Fox's Fox Illusion Only 1 frame.
- Fox's Reflector The first attack frame.
- Falco's Falco Phantasm Only 1 frame.
- Wolf's Reflector, First 6 frames.
- Zero Suit Samus Flip Jump Only 1 frame
- Marth's Dolphin Slash First 5 frames (5th frame is also hit frame, Brawl only).
- Mr. Game & Watch's Fire From frame 9 until frame 13.
- Sonic's Up smash before the hitbox comes out.
- Pikachu's Thunder, Beginning frames when Thunder strikes Pikachu.
- Zelda's Farore's Wind right before Zelda teleports.
- Sheik's Vanish right before Sheik teleports.
- Lucario's Double Team, During all the counter frames as well as the counterattack. Since it has true invincibility frames, it can protect Lucario from Final Smashes unlike other counters (though he still can't counter them).
- Jigglypuff's Rest, Approximately 20 frames after it's released, while its eyes are closing. (During the attack hitbox)
- Olimar's Pikmin Pluck
- All Final Smashes grant invincibility at the start of it.
Overall, invincibility is generally a good thing. However, one negative aspect is that on the Brinstar and Norfair stages, characters will pass straight through the lava, rather than sustaining damage and bouncing back up.