Hoenn Catastrophe • Emerald Hack • Completed English Version

Pokemon Sirius

Pokemon Sirius is a completed English Pokémon Emerald ROM hack from the Pokemon Vega Team. It takes place in Hoenn three years after a meteor disaster tears the region apart, filling the world with Meteoric Pokémon, strange new Fakemon, harder battles, and one of the most influential old-school fan-hack atmospheres around.

The key thing to understand is that Sirius is not some tiny side project riding Vega’s name. It is one half of the original Altair / Sirius pair, and together those games laid the groundwork for Vega. If you like classic hacks with identity, challenge, and a little rough-edged ambition, Sirius still has that pull.

☄️ Hoenn after the meteor disaster
🧪 Emerald-based counterpart to Altair
🧬 181 new Pokémon + 56 newer-gen mons
🎵 Custom soundtrack and new moves
⚔️ Tough trainer fights and rematches
🏁 Extensive postgame content
🌌 Meteoric Pokémon and Fakemon
📱 Playable on mobile & desktop
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About Pokemon Sirius

The main thing worth correcting about Sirius is what kind of hack it actually is. It is not a prequel to Altair, and it is not a completely unrelated Vega spin-off. Sirius and Altair are the paired versions of the same core adventure, with version-exclusive Pokémon differences much like the mainline games. Vega comes later.

That matters because Sirius makes more sense when you think of it as an old-school counterpart release built on Pokémon Emerald. You are still travelling through a recognisable version of Hoenn, but the region has been battered by the Hoenn Catastrophe, which gives the whole journey a harsher tone and a more unusual Pokédex than standard Emerald ever had.

It is also one of those hacks that helped define a lane for later projects. The Fakemon are a huge part of the appeal, but Sirius is not only about novelty monsters. It also has a real atmosphere, memorable custom music, long-term progression, and the kind of difficulty curve that asks you to actually think instead of sleepwalking through route fights.

Counterpart-version structure Sirius is meant to sit beside Altair, not beneath it. The two games mostly share the same backbone but diverge through version-exclusive encounters and related details.
Classic but altered Hoenn The map and progression still feel tied to Hoenn, but the catastrophe framing, changed wildlife, and route differences make the adventure feel much less vanilla.
Historical ROM-hack weight This is one of the big older projects people still bring up when talking about Fakemon-era hacks and the road that eventually leads to Vega.
Not built for autopilot Smart battles, broad rosters, and a tougher curve mean Sirius rewards team planning more than a casual Emerald replay does.

The Hoenn Catastrophe and why the world feels different

Pokemon Sirius starts with one of the better old hack premises: three years after Brendan becomes Champion and retires, Hoenn is slammed by a meteor disaster. The event leaves parts of the region devastated, wipes out some familiar species, and introduces strange new creatures known as Meteoric Pokémon. That alone gives Sirius a stronger narrative frame than a lot of older hacks that simply swap sprites and call it a day.

You still begin in Littleroot Town and set out on a trainer journey, but the overall feel is not “standard Emerald with a few extras.” It is more like a damaged, reshaped version of Hoenn where the ecosystem has been knocked sideways and the Pokédex itself has become part of the mystery. Professor Birch’s request to document the new species makes sense inside the plot instead of feeling bolted on.

The world is also tied into the wider Altair / Sirius / Vega line. That means Sirius has a little extra payoff for players who enjoy seeing how one hack feeds into another, but it still stands on its own as a full run if you only want to play one version.

☄️ Meteor disaster hook

The catastrophe does real work for the setting. It changes the atmosphere, the creature roster, and the sense of what you are exploring.

🌍 Familiar region, different feeling

This is still recognisably Hoenn, but it feels harsher, stranger, and less settled than the vanilla region you already know.

📘 Pokédex with story value

Cataloguing new species fits naturally because the region’s wildlife has actually changed, instead of the game just handing you a busywork objective.

🌌 Leads cleanly into Vega

If you like seeing the roots of later famous hacks, Sirius is part of that lineage rather than just borrowing the name.

The right way to sell Sirius: it is a post-catastrophe Emerald counterpart hack with Fakemon and bite, not a made-up “prequel” and not a thin generic difficulty mod.
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Fakemon, moves, music, and the features that carry the page

Sirius has enough real feature depth that the page does not need to pad itself with vague hype. Public release notes consistently describe it as an Emerald-based English hack with 181 new Pokémon, 56 Pokémon from newer generations, 70 new moves, 87 later-generation moves, custom music, trainer rematches, and extensive postgame content.

That is a lot, but what matters more is how it feels in play. Sirius is one of those hacks where the roster and soundtrack do a lot of the heavy lifting for identity. Even when the broad route structure still echoes Emerald, the Pokémon selection and battle rhythm keep reminding you that you are playing something different.

What stands out most

  • Huge custom roster: Fakemon and Meteoric species are the headline draw, but the extra newer-generation inclusions help team-building feel broader too.
  • Version-exclusives matter: Sirius is not just Altair with a title swap. The two are counterpart versions, which gives replay value to the pair.
  • Custom soundtrack: older hacks live or die on atmosphere, and Sirius has enough of its own musical flavour to stay memorable.
  • Long tail after the League: the postgame and extra facilities make it feel like more than a one-and-done novelty run.
Good for Fakemon fans If your favourite part of older hacks is discovering unfamiliar monsters rather than just replaying a harder base game, Sirius delivers on that immediately.
Good for long runs Between rematches and postgame content, the game gives you reasons to stay beyond the badge march and the first League clear.
Good for paired-version nerds Players who like comparing counterpart versions get more out of Sirius than out of a lot of one-off hacks.
Still proudly old-school Sirius has ambition and flavour, but it still feels like a classic GBA-era fan project rather than a slick modern decomp showcase.

How hard Sirius is, and who it is best for

Pokemon Sirius is generally remembered as a challenging hack. It is not impossible, but it is definitely built for players who do not mind some grinding, smarter team planning, and the occasional fight that punishes a sloppy lineup. Compared with vanilla Emerald, this is a real step up.

That tougher feel is part of the appeal. Sirius belongs to the older school of ROM hacks where difficulty is not always smoothed over for convenience. If you like that style, the extra bite helps the game stand out. If you want a very breezy browser playthrough, this is not really the one to start with.

Best for

  • Players who enjoy Fakemon and do not mind a bit of grind.
  • Fans of classic ROM-hack history who want to see the road leading to Vega.
  • Anyone who likes postgame content and version-exclusive replay value.
  • People who want Emerald bones with a harsher, stranger atmosphere.

Good tips before starting

  • Build coverage early instead of trying to force one overlevelled carry through every fight.
  • Catch more than you think you need — the strange roster is part of the point of playing Sirius.
  • Save often before big battles and route pushes, especially if you are learning the Fakemon blind.
  • Use the browser save icon as your main backup so you are not relying only on in-game saves.
Simple expectation check: Sirius is a harder classic-style hack, not a polished “quality-of-life first” modern comfort run. That is exactly why some players still love it.
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Frequently asked questions

What is Pokemon Sirius?

Pokemon Sirius is a completed English Pokémon Emerald ROM hack from the Pokemon Vega Team. It is the counterpart version to Pokemon Altair and is set in Hoenn after the Hoenn Catastrophe.

Is Pokemon Sirius based on Emerald?

Yes. It is based on Pokémon Emerald.

Is Sirius different from Altair?

Yes, but mainly through version-exclusive Pokémon and related counterpart differences. They are paired versions of the same core adventure rather than totally separate games.

Is Pokemon Sirius finished?

Yes. The English release is generally listed as completed, with the translated version last updated in late 2020.

Is Pokemon Sirius hard?

Yes. It is noticeably tougher than vanilla Emerald and is better suited to players who enjoy a challenge.

Can I play Pokemon Sirius on mobile?

Yes. RomHaven’s browser emulator works on phones, tablets, and desktop, so you can jump in without setting up a separate emulator first.

If you liked this, try these

More Pokémon ROM hacks Browse the wider RomHaven library if you want another browser-ready project after Sirius. Pokemon Obscura An Emerald-based story project with a completely different tone if you want something newer after this old-school classic. Pokemon The Unown King A shorter myth-heavy Emerald adventure if the stranger lore side of Sirius is what grabs you most.
Pokemon Sirius — play online now Explore post-catastrophe Hoenn, meet strange new species, and try one of the classic Emerald-era Fakemon hacks.
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