-279,Prevents all friendly Pokémon from fainting this turn.,No Pokémon on the user's team can have its [HP]{mechanic} reduced below 1 until the end of this turn.
-280,Averages Defense and Special Defense with the target.,Averages the user's Defense and Special Defense with the target's.
-281,Averages Attack and Special Attack with the target.,Averages the user's Attack and Special Attack with the target's.
-282,Swaps every Pokémon's Defense and Special Defense for 5 turns.,Every Pokémon on the field has its Defense and Special Defense swapped for the next 5 turns.
-283,"Inflicts damage based on the target's Defense, not Special Defense.","Inflicts regular damage, but always uses the target's Defense for damage calculation, never its Special Defense."
-284,Inflicts double damage if the target is Poisoned.,Inflicts regular damage. This move's power is doubled against Pokémon that are Poisoned.
-285,Raises the user's Speed by two stages and reduces the user's weight.,Raises the user's Speed by two stages and reduces weight.
-286,Inflicts a random status effect on the target for 3 turns.,Inflicts a random status effect on the target for 3 turns. This move will fail if Gravity is in effect.
-287,Held items cannot be used for five turns. (?),Held items cannot be used for five turns. (?)
-288,Grounds Flying and Levitating Pokémon.,"Removes [Flying]{type}-type and [Levitating]{ability:Levitate} Pokémon's immunity to Ground, similar to as in [Gravity]{move}."
-289,Always results in a critical hit.,Always results in a critical hit.
-290,Not yet known. [[effect 290]],Not yet known. [[effect 290]]
+279,Prevents any multi-target moves from hitting friendly Pokémon this turn.,"Moves with multiple targets will not hit friendly Pokémon for the remainder of this turn. If the user is last to act this turn, this move will fail.
+
+If the user successfully used [Detect]{move}, [Endure]{move}, [fast guard]{move}, [Protect]{move}, or [wide guard]{move} on the last turn, this move has a 50% chance to fail.
+
+This move cannot be selected by [Assist]{move} or [Metronome]{move}."
+280,Averages Defense and Special Defense with the target.,Averages the user's unmodified [Defense]{mechanic} with the target's unmodified Defense; the value becomes the unmodified Defense for both Pokémon. Unmodified [Special Defense]{mechanic} is averaged the same way.
+281,Averages Attack and Special Attack with the target.,"Averages the user's unmodified [Attack]{mechanic} with the target's unmodified Attack; the value becomes the unmodified Attack for both Pokémon. Unmodified [Special Attack]{mechanic} is averaged the same way.
+
+This effect applies before any other persistent changes to unmodified Attack or Special Attack, such as [Flower Gift]{ability} during [Sunny Day]{move}."
+282,All Pokémon's Defense and Special Defense are swapped for 5 turns.,"For five turns (including this one), every Pokémon's [Defense]{mechanic} and [Special Defense]{mechanic} are swapped."
+283,"Inflicts damage based on the target's Defense, not Special Defense.","Inflicts regular damage. Damage calculation always uses the target's [Defense]{mechanic}, regardless of this move's damage class."
+284,Inflicts double damage if the target is Poisoned.,"Inflicts regular damage. If the target is [poisoned]{mechanic}, this move has double power."
+285,Raises the user's Speed by two stages and halves the user's weight.,Raises the user's [Speed]{mechanic} by two [stages]{mechanic:stage}. Halves the user's weight; this effect does not stack.
+286,Moves have 100% accuracy against the target for three turns.,"For three turns (including this one), moves used against the target have 100% [accuracy]{mechanic}, but the target is immune to [Ground]{type} damage. Accuracy of one-hit KO moves is exempt from this effect.
+
+This effect is removed by [Gravity]{move}. If Gravity is already in effect, this move will fail."
+287,Negates held items for five turns.,"For five turns (including this one), passive effects of held items are ignored, and Pokémon will not use their held items."
+288,Removes any immunity to Ground damage.,"Inflicts regular damage. Removes the target's [immunity]{mechanic:immune} to [Ground]{mechanic} damage. This effect removes any existing Ground immunity due to [Levitate]{ability}, [Magnet Rise]{move}, or [Telekinesis]{move}, and ignores the target's [Flying]{type} type when calculating damage it takes.
+
+If the target isn't immune to Ground damage, this move will fail."
+289,Always results in a critical hit.,Inflicts regular damage. Always strikes a [critical hit]{mechanic}.
+290,Deals splash damage to Pokémon next to the target.,"Inflicts regular damage. If this move successfully hits the target, any Pokémon adjacent to the target are damaged for 1/16 their max [HP]{mechanic}."