Being buried is a status condition that can be inflicted by attacks with a bury or plunge effect. It debuted in Super Smash Bros. Melee, and has appeared in every subsequent game. A buried character is embedded in the ground, with the visible part of their body surrounded by churned dirt, and is then unable to take action until the status wears off. Burying generally lasts longer as the target's damage percentage increases, but can be escaped faster via button mashing.
Any fighter on the ground hit by an attack with a bury effect will be buried. In Melee, Super Smash Bros. 4 and Super Smash Bros. Ultimate, a character that is lying down cannot be buried, unless they are lying down due to Snake's down throw; however, a character who has tripped can be buried. In Super Smash Bros. Brawl, characters lying down on the ground can be buried. If a fighter cannot be buried, they simply take knockback as usual from the bury attack. In all games, buried characters cannot be grabbed.
In Melee, very few attacks can bury characters, with the only one belonging to a playable character being Donkey Kong's Headbutt. It has since become increasingly more common in latter games, with examples of new attacks that can cause it being Villager's down smash, Zero Suit Samus' automatic Flip Jump stomp from Smash 4 onward, Mr. Game & Watch's down smash in Ultimate, and King K. Rool's down throw. The Pitfall item uses a plunge effect, which drops characters through soft platforms if they can be buried, but otherwise behaves identically to the bury effect.
In Ultimate, the support spirit skill Bury Immunity prevents the equipped fighter from being buried.
In Melee and Brawl, a buried character simply remains stuck in one animation frame, with no visual indication of how much time they have left to escape. In Smash 4, however, they shake when button mashing to escape faster. Ultimate, in addition to keeping this visual effect, adds others that better indicate how close a buried character is to escaping; when 30% of the initial bury duration has passed, small portions of dirt splash out of them, and when 60% of the duration has passed, the character flashes yellow with larger and louder portions of dirt splashing out of them. If buried by a throw, the small dirt splashes appear immediately, with the latter effect instead happening when 33.3% of the initial bury duration has passed.
In Ultimate, characters have two buried poses: upright and upside down. Fighters are normally buried upright, but King K. Rool, R.O.B., and Banjo & Kazooie's down throws bury the thrown fighter upside down. The latter pose is also used during Lucas's down throw, although it does not cause the buried condition (in Smash 4, it uses a character's grabbed animation rather than a specific buried pose). Being buried upright or upside down affects the hurtbox placement of the buried character, so a character that is buried upright might not get hit by an attack that would hit them buried upside down, and vice versa.
The boss Rathalos (but not as an Assist Trophy) is affected by Pitfalls, having its own unique buried appearance with a very large amount of churned dirt surrounding it. It cannot be buried by any other attacks, however.
In Melee, the formula for bury frames is
From Brawl onward, the formula is changed to
As a result, in addition to characters' rank in a battle being a more important factor for bury time, attacks also have their bury time influenced by their knockback, rather than simply the opponent's percent.
In Ultimate, characters with burying down throws use different formulas for them:
For these formulas, p is the opponent's percent before the damage is dealt, instead of after. Due to knockback and rank not being factors whatsoever, the bury time of these throws is much less variable and thus easier to calculate.
In all games, a character's bury time ending causes them to automatically jump with some additional ending lag, effectively adding some vulnerable time after the bury. This ending lag lasts 16 frames in Melee, 11 frames in Brawl and Smash 4, and 12 frames in Ultimate. However, in Melee, buried characters are given invincibility for 18 frames upon escaping, preventing guaranteed followups; this is not the case in later games, allowing burying moves to be combo starters and even set up various kill confirms.
Knocking characters out of burying
In Melee, buried characters remain stuck on the ground until the effect wears off or the ground disappears, and attacks do not affect its duration, even if they deal extremely high knockback. From Brawl onward, hitting the character with an attack that deals at least a certain amount of knockback (100 units in Brawl and Smash 4, and 90 units in Ultimate) causes them to escape the bury and be launched as usual. In Brawl and Ultimate, the amount of knockback taken does not get reduced, allowing for reliable, early KO setups on buried characters; however, in Smash 4, it is equal to 0.7× of the knockback that would have been inflicted otherwise, drastically weakening the effectiveness of such setups.
In Ultimate, attacks that hit buried opponents without unburying them have their knockback "stored" and applied when the effect wears off, including neutral attacks and meteor smashes, and even other status conditions such as freezing, allowing even more followups out of a bury if the opponent cannot escape quickly enough.
Bury Tech Situation Storage
Due to new mechanics relating to knockback's interactions with buries in Ultimate, there are some instances where knockback storage will result in tech situations being stored. This is known as Bury Tech Situation Storage, or BTSS. As of version 13.0.0, the glitch was patched out.
Attacks stored that result in a launch angle of 0° or 180° (including the Sakurai angle at lower percentages), while an opponent has their control stick positioned in the upper half of the stick radius, cause the glitch to occur. The reason why this happens is due to buries storing knockback, and ASDI being triggered on release when the stick is held upwards at the end of the bury. This causes opponents to be forced into the tech situation. Due to ASDI being required, bury throws are unaffected by BTSS. Any buried state, as long as it isn't caused by a throw, will cause this to occur. Thus, anything from Pitfalls to Flip Jump buries can potentially cause this. Unusually, the interaction only occurs with buries, and no other state.
This technique can be used as a counter to mashing using directional inputs, although it can be avoided. Some examples include only using the lower half of the stick radius, or simply button mashing, although the latter is considered suboptimal. However, against players rotating the stick completely, it has a decently high chance of occurring. Almost every neutral attack in the game can cause this to occur due to their low knockback and Sakurai angles, giving easy access to the technique. However, there are many other options in the game that have the possibility of causing this, due to the abundance of the Sakurai angle. Since the Sakurai angle is locked to 0° prior to 60 KB, this makes an otherwise rare occurrence very easy to execute.
Opponents being able to miss techs right in front of a player gives them easy access to lock confirms, especially if they can also cover tech options. As a result, BTSS has very high reward should it occur in the right circumstances. Characters such as King K. Rool can also force it to occur with moves like down aerial pre-tumble, allowing for exceedingly high damage output that also cover tech options with alternate, reactable combo routes. However, the RNG-based inconsistencies of the technique also make it difficult to plan and prepare for. Without having a specific combo route for whether it works or doesn't, BTSS is more of an inconvenience than a benefit.