Pokémon Ruby and Sapphire

This page details bugs of Pokémon Ruby and Sapphire.

To do: Cover the Mail memory slot bugs and associated effects (such as tile corruption and item duplication); a decent summary can be found here.

Protect Bug#

Protect, Detect, and Endure are moves that will always succeed on the first use, but have a halved success rate with each consecutive use. Rather than calculating the probability on the fly as earlier generations did, Generation III uses a fixed table that contains probabilities for the first four consecutive uses (100%, 50%, 25%, and 12.5%, respectively). Apparently, Game Freak did not anticipate that someone might be lucky enough to successfully use Protect four times in a row, as the fifth and any consecutive uses will read the data that comes after the probability table, leading to very erratic and seemingly random success rates.

A complete table can be found here. Note that starting from turn 53 the values differ between Ruby & Sapphire, FireRed & LeafGreen, and Emerald.

Ruby & Sapphire have an additional bug: Protect, Detect, and Endure have a 1 in 65,536 chance of failing even when the move should succeed (including on the first use) due to the wrong operator being used. This was fixed in FireRed, LeafGreen, and Emerald.

National Pokédex bug#

While obtaining the National Pokédex in any of the mainline Pokémon games usually does not require event-exclusive Pokémon, Ruby & Sapphire have a bug and exclude Chikorita from the National Pokédex requirement instead of Ho-Oh and Lugia, which are Pokémon that can only be obtained as trades from Pokémon Colosseum and Pokémon XD: Gale of Darkness respectively. This was fixed in FireRed & LeafGreen and Emerald.

Roaming Pokémon encounter bug#

Lose a battle to a trainer who has 2 or more Pokémon, then immediately, without getting into any other battles, encounter the roaming Latias/Latios. Defeat the Latias/Latios, and the game will "send out" the next Pokémon that would be in the trainer's team that was lost against previously. These Pokémon can flee like Latias/Latios, but they can be caught with a Poké Ball.

This bug happens because the roaming Latias/Latios encounter does not properly clear all 6 of the slots used for enemy Pokémon in the game's memory before adding in the new set of enemy data (as all other encounters do), and instead only replaces the first slot with the Latias/Latios while leaving the rest unchanged from the previous battle.

Most Pokémon caught this way will trigger a checksum mismatch and turn into Bad EGGs. Pokémon caught from Battle Tower trainers do not do this, so this is an easy way to quickly catch level 100 Pokémon.

This glitch does not work in Emerald.

Roaming Pokémon IV bug#

The IVs for the roaming Latias/Latios are generated and saved to the save file the moment you watch the TV broadcast after beating the game. However, when encountering the roaming Latias/Latios, only its HP IVs will be correct; its attack IVs can only be a maximum of 7, and all other IVs are guaranteed to be zero.

This bug happens due to an improper cast when the roaming Pokémon's IVs are transferred from the save file to the wild encounter data; the 32-bit value containing the IVs are shoved into an 8-bit value, causing all bits beyond the first 8 bits to be truncated.

The bug also affects the roaming legendary beasts in FireRed & LeafGreen. It was fixed in Emerald.

Wobbuffet Endless Battle Bug#

In the Generation III games, if two Wobbuffet both holding Leftovers face each other in a battle, the battle becomes endless.

Wobbuffet does not have any attacks that can directly damage the opponent, it can only use Counter or Mirror Coat to reflect the damage taken back to the user. Even if Wobbuffet runs out of PP and gets forced to use Struggle, Struggle does less damage than the amount healed by Leftovers each turn thanks to Wobbuffet's low Attack and high HP, so two Wobbuffet can never knock each other out using Struggle.

This becomes a problem in Generation III due to Wobbuffet's new Ability Shadow Tag, which prevents the opponent from switching out. This removes the last option of ending the battle, and as such, the battle never ends until you turn off the console.

The Generation IV games had two changes to prevent this kind of situation: first, two Pokémon that both have Shadow Tag will cancel out each other's effects, allowing each Pokémon to switch out, second, Struggle's recoil damage was greatly increased so it can no longer be healed off by Leftovers.

Bard “CELEBI” bug#

The Bard, an NPC that recites sentences created with the easy chat system using a rudimentary TTS engine, cannot pronounce the word “CELEBI” in the USA version (and the word appears very slowly). The Japanese and European releases are unaffected. In the following videos, the third word has been replaced with “セレビィ”/“CELEBI”.

Shed Skin Nightmare Bug#

In Ruby & Sapphire, the ability Shed Skin does not remove Nightmare status, so if a Pokémon is cured from sleep due to Shed Skin, it will continue taking damage from Nightmare every turn despite being awake. This was fixed in FireRed & LeafGreen and Emerald.

Pay Day Bug#

In Ruby & Sapphire, the message displayed when using Pay Day does not take into account the effects of the Amulet Coin and will display the wrong amount of money in this case. This is purely a visual bug, the correct amount of money is still gained after battle. This was fixed in FireRed & LeafGreen and Emerald.