Ghost Grey: Getting Started (Patch, Version & First Hour)

Short answer: Ghost Grey is a binary-only Pokémon FireRed hack by Joey Zeed. You patch a clean FireRed (USA) Rev 0 cartridge dump with the author's BPS file, and you should end up with a 32 MB ROM whose CRC32 is 737A7A12. The current release is v1.0.4, and that matters, because most of the Ghost Grey documentation floating around describes v1.0.1 and the game has moved since.

What you are patching

Rev 0 is not a suggestion. FireRed shipped in multiple revisions and the patch will not apply cleanly to the wrong one. Check the CRC32 of your dump before you patch, not after.

Patching, in order

1. Dump your own FireRed (USA) Rev 0. Verify CRC32 DD88761C first.
2. Get the patch from the author's own link in the PokéCommunity release thread or from Hackdex. Download the patch, never a pre-patched ROM.
3. Apply it with a BPS applier such as Flips, or any tool that follows the reference implementation.
4. Verify the output. You want 33,554,432 bytes and CRC32 737A7A12. If you have a different size or hash, either the base ROM was the wrong revision or the applier mishandled BPS offsets.

The retired build: GhostGrey02.bps patches to CRC32 DCAC3F32. That is the older version. If your patched ROM hashes to DCAC3F32, you are on the previous release, not the current one.

Why the version matters

Ghost Grey is actively maintained, and the documentation ecosystem has not kept up:

• The fan docs site (ghostgrey.jruco.workers.dev) and the pokerex.io extraction both describe v1.0.1.
• The hack listing sites track v1.0.2.
• The current release is v1.0.4.

A patch that only claims boss and movepool fixes can still move base stats, TM and HM compatibility, wild encounter tables, and sprite art. That means older documentation is not merely incomplete -- some of it is confidently wrong about the current build. When a guide tells you a Pokémon is in a route and you cannot find it, check which version that guide is describing before you assume you are doing something wrong.

If a newer patch lands while you are mid-playthrough, re-verify. Documented claims from an earlier version do not automatically carry forward.

What is actually in it

The dex is not Kanto's, and this catches people out. Ghost Grey has a rebuilt regional dex: the list starts at Rowlet and runs to a regional number of 410, and 132 of the 291 species are original to the hack -- Spiritle, Wickortle, Lichtoise, Shuderbug, Spewkpa, Vivillain, Poltersect and a hundred more you have never seen.

The 159 official species that survive are drawn from every generation. Gen 1 contributes only 31 of them, and the missing ones are the ones you would notice first: no Pidgey, Rattata, Caterpie, Zubat, Geodude, Abra, Mankey, Magikarp, Eevee, or any of the three base Kanto starters. Their evolved forms sometimes remain -- Blastoise, Charizard, Venusaur, Gyarados and Alakazam are all in the dex -- which tells you the author kept the payoffs and cut the filler.

Pikachu exists as Pikaboo, which evolves into Gorochu at level 26. Gorochu is the evolution that was designed for Red and Green and cut before release. Ghost Grey gave it a home.

That is a FireRed hack with a CFRU-era engine underneath, which is how it has a Fairy type, modern species, and Gen-4-and-later evolutions at all. For what changed numerically -- including nine type-chart deviations -- see what's different from vanilla.

Five things to know before you start

1. There are no EVs. Every species' EV yield in the ROM is empty. Stop counting wild encounters for stat gains; that system is not here. IVs still exist and can be improved with a Bottle Cap, whose item text admits the concept is opaque.

2. There are no trade evolutions. The ROM's evolution table contains zero trade methods and no Link Cable. Everything evolves by level, by stone, or by friendship. If a species evolved by trade in the official games, Ghost Grey found a different way -- and while you are here, assume nothing about what evolves into what. See the evolution guide.

3. Hidden items outnumber visible ones. 219 placements are hidden versus 198 visible. The Itemfinder is worth a detour the moment you can get it, because more than half the items in this game will never be visible on the ground.

4. Five of the six evolution stones are sold in Saffron City. Sun, Dusk, Harvest, Abyss, and Avarice Stones are all purchasable there. Moon Stones are a gift, not a purchase. Details in the evolution guide.

5. Expect a long game. The Elite Four sit between level 69 and 75, one late trainer sits at level 65, and the final fights are at level 95 to 99. This is not a hack that ends around level 50.

Your starter

Three starters, chosen in Oak's lab, and every one of them is a Ghost dual-type -- which tells you what kind of game this is. They are also the first three lines of the regional dex, in order:

Rowlet and the Litwick line are official species. Spiritle is original to this hack and the only starter line that is, so if you want the one you cannot get anywhere else, take the water starter. Your choice follows you all the way to the end: the champion's team carries a different Pokémon depending on which of the three you picked -- Lichtoise for water, Chandelure for fire, Decidueye for grass.

Your first hour

The opening follows Kanto's geography: Pallet Town, north up Route 1, into Viridian City, then Route 2 and Viridian Forest before Pewter City. Wild levels in the earliest areas are low -- Route 1 and 2 run around level 2 to 5, Viridian Forest around 3 to 7 -- so the first hour is ordinary FireRed pacing.

Worth picking up on the way:

Buying an Exp. Share in Viridian City before the first badge is the single biggest quality-of-life decision available early, because the level curve gets long later on. The Amulet Coin in the same shop doubles battle money while the holder fights, which pays for the stone shopping you will want in Saffron.

Pewter City hands you HM01 and HM05 as gifts, so do not walk out of town without talking to everyone.

When you get stuck

Three things account for most "I am stuck in Ghost Grey" situations:

1. A locked door. There are ten keys and access cards, several of them inside BrunoCorp. See key items.
2. A hidden item you cannot see. Sweep with the Itemfinder; more than half the placements are invisible.
3. A route you have not been given a reason to walk. The badge order does not follow the map's geography -- badges one, six and eight are story grants, not gym fights. See the walkthrough.

What this guide does not claim

It does not rank the three starters or tell you which one the lab offers first, and it does not claim to have read the starter script. The three lines above are identified two ways -- they are the first three lines of the regional dex, and the champion's team changes to exactly one of their final forms depending on which one you took -- and those two pieces of evidence agree. It also does not claim any completion time, since that depends entirely on how much of the optional content you chase.

It does not host, link to, or describe where to obtain a FireRed ROM. Dump your own cartridge.

Related: the walkthrough, key items, what's different from vanilla, the evolution guide.