Nuzlocke Rules for Soulgold

Soulgold does not ship a built-in Nuzlocke mode, and that is the honest starting point rather than a gap in this page. There is no rule enforcement screen, no encounter locking, and no fainted-Pokémon handling in the game's own menus, so a Nuzlocke here is a ruleset you apply to yourself. What follows is a workable version of that, plus the hack-specific details that decide whether a run survives.

A ruleset that fits the hack

• One catch per area. In Soulgold, the sensible unit is the game's own mapped area rather than numbered routes only, since towns, caves and interior routes all hold encounters. The Locations pages and the Encounter Finder cover the whole region if you want to plan the catch before you walk in.
• Faint means gone. Release it or box it permanently. Held items come back before it goes.
• Nickname everything. Without a built-in tracker, the nickname is what reminds you which Pokémon used which area's catch.
• Dupes: if you have already caught something from that evolutionary family, keep looking.
• Shinies: always catchable, even if the area's encounter is spent. At 1/256 odds, turning shinies down would be worse than skipping a route.

The four details that actually decide runs

Soft level caps, not hard ones. Soulgold's caps are tied to badges and reduce experience gain sharply once you reach them rather than blocking it. That makes accidental overlevelling much less likely than in the official games, but it also means a run that falls behind stays behind, so plan grinding before a Gym rather than during it. The numbers are on the Walkthrough & Progression Guide.

Hard mode is a Nuzlocke multiplier. Gym battles become doubles unless another setting forces singles, which changes which Pokémon are actually safe to bring. If you are choosing between a standard and Hard run, the difference matters far more here than the stat numbers suggest.

Boss Pokémon do not break runs the way legendaries usually do. Some legendary fights use multiple health bars and are genuinely dangerous, but you are guaranteed to catch them with any ball once they are defeated. In Nuzlocke terms a legendary encounter is therefore a real risk that pays out reliably, instead of a coin flip that can fail after the fight is already won.

No revive-by-legendary escape hatch. There is no shiny sandwich, no affection-based survival system carrying a Pokémon through a fatal hit. Death is death.

Practical running order

1. Decide the run before you leave New Bark. Options are settled at New Game and the hack's settings are not a live toggle for everything.
2. Bank the Exp. Share and the Candy Jar early; the Candy Jar is the cleanest way to keep a rotating party level-appropriate without grinding a single carry.
3. Use the Battle Factory from your third badge onward for ability changes and IV feathers. Both are cheap ways to make a rebuilt team viable after a loss.
4. Check Trainer Battles before each Gym rather than learning the teams the expensive way.
5. Treat the postgame as a separate run. Kanto Leaders sit at levels 57-69 with a 70 cap behind the Champion, so an under-levelled party that survived Johto will not survive Kanto.

If you want a harsher version

Drop the Dupes clause, require the first encounter in every area, ban healing items in battle, and cap your party at the current badge's level cap rather than the soft cap the game applies. That last one turns Soulgold's soft caps into a hard rule of your own making, which is the closest thing to a built-in challenge mode the hack currently offers.