Dragon/Steel is built from two components that almost never overlap in what they resist, and the one place they do overlap (Dragon's own weakness to itself) is a case of Steel directly canceling Dragon's biggest liability rather than stacking with it. The result is one of the smallest weakness lists of any dual typing in the game: two types, full stop, out of eighteen possible attacking categories.
The Resistance Math, Type by Type
Steel on its own resists Normal, Grass, Ice, Flying, Psychic, Bug, Rock, Dragon, and Steel, and is immune to Poison — the single largest resistance count of any type in the game. Dragon on its own resists Fire, Water, Electric, and Grass. Multiplying the two together: Grass appears on both lists, so it resists at 0.25x rather than 0.5x. Fire, Water, and Electric are Dragon-only resistances that carry through unchanged since Steel doesn't touch them negatively. Normal, Ice, Flying, Psychic, Bug, and Rock are Steel-only resistances that carry through unchanged since Dragon doesn't touch them negatively. Dragon-type damage against a Dragon/Steel target is the interesting case: Dragon itself is weak to Dragon at 2x, but Steel resists Dragon at 0.5x, and multiplying a 2x weakness by a 0.5x resistance produces a flat 1x — neutral damage, with the two effects canceling exactly. Poison is a hard 0x immunity from Steel alone, unaffected by Dragon having no opinion on Poison either way.
The Two Weaknesses, and Only Two
After all of that resistance stacking, Dragon/Steel has exactly two weaknesses on the entire eighteen-type chart: Fighting and Ground. Neither component type resists either of them, and neither cancels the other out, so both come through at a clean 2x. That's it — no hidden 4x weakness, no secondary type interaction working against the defender anywhere else on the chart. Compare that to a typing like Ice/Ground, which nominally looks strong on paper but stacks a 4x Water weakness from both types independently disliking it; Dragon/Steel has no such compounding weakness anywhere.
| Category | Types |
|---|---|
| Resists at 0.5x | Fire, Water, Electric, Normal, Ice, Flying, Psychic, Bug, Rock |
| Resists at 0.25x | Grass |
| Immune (0x) | Poison |
| Neutral (1x, cancelled weakness) | Dragon |
| Weak at 2x | Fighting, Ground |
Case Study: Dialga
Dialga's 100/120/120/150/100/90 spread puts its bulk on the physical side exactly where the typing's two weaknesses (Fighting, Ground — both physical categories) need the most cushioning, and Pressure forces opposing attackers to burn PP faster against it. Roar of Time as a signature Dragon STAB and the ability to run either a bulky support set with Stealth Rock or a Choice Specs breaker set both function because the typing rarely needs to switch out reactively — most of the metagame simply can't threaten it on the type chart alone, only through raw power or the two confirmed weaknesses.
Case Study: Duraludon and Archaludon
Duraludon runs a thinner 71/95/115/120/70/85 spread that trades some bulk for Speed relative to Dialga, leaning on Stealth Rock and Body Press (a move that uses Defense instead of Attack for its damage calculation) to convert its own defensive investment directly into offense. Its evolution Archaludon keeps the Dragon/Steel typing but adds Stamina, an ability that raises Defense by one stage every time it's hit by a physical attack — a direct answer to the typing's own physical-side weaknesses, since a Fighting- or Ground-type attacker that doesn't OHKO on the first hit makes every subsequent hit weaker as Archaludon's Defense climbs in response.
How Stamina Archaludon Anchors a Rain Team
On Rain, Archaludon's Electro Shot (a Special Electric move that raises Sp. Atk on use, and fires immediately rather than charging when Rain is active) turns it into a dual-purpose piece: Stamina handles the physical side of its own weakness profile passively, while Rain's damage boost to its Electric STAB and the Water-immunity-adjacent safety of not caring about incoming Water coverage (Steel resists nothing about Water directly, but Dragon/Steel's overall resistance spread means Rain-boosted Water attacks are rarely the thing actually pressuring it) lets it act as the team's physical damage control piece. Opposing physical wallbreakers that would otherwise steamroll a Rain team's frailer attackers instead run into a Pokémon that gets tankier the longer they attack it, buying the rest of the team time to close out the game with Rain-boosted special offense.
Case Study: Hisuian Goodra
Hisuian Goodra swaps out base Goodra's Dragon/Poison split for Dragon/Steel, and the typing change alone is responsible for most of its competitive relevance — base Goodra's Poison half added a Ground and Psychic weakness on top of Dragon's baseline, while Hisuian Goodra trims the weakness list down to the same clean Fighting/Ground pair every other Dragon/Steel Pokémon shares, while keeping a genuinely enormous special bulk stat (110 base Sp. Def) that lets it check special Dragon-types other members of the archetype can't handle as comfortably.
The Broader Lesson: Two Weaknesses Is the Threshold
Most competitively relevant defensive typings land somewhere between two and four weaknesses; Dragon/Steel sits at the floor of that range while also picking up nine-plus resistances and an immunity, which is a resistance-to-weakness ratio almost no other typing matches. The practical teambuilding implication is that any Dragon/Steel Pokémon with even moderate bulk becomes a full-time answer to a huge slice of the metagame rather than a situational check, and the only real cost of using one is making sure the rest of the team covers Fighting and Ground — a coverage requirement narrow enough that most teams meet it by accident through unrelated typing choices anyway.
The Offensive Trade-Off Nobody Talks About
Dragon/Steel's defensive profile is close to best-in-class, but it comes with a real offensive cost that gets glossed over: Steel STAB is resisted by Steel, Water, and Fire, while Dragon STAB is resisted by Steel and Fairy — meaning any opposing Steel-type wall resists both of a Dragon/Steel Pokémon's primary STAB options simultaneously. That's why Dialga and Archaludon both carry coverage moves outside their dual STAB (Fire Blast on Dialga, Electro Shot on Archaludon) rather than leaning purely on same-type attacks the way a typing with less-overlapping resistances might. The defensive strength of Dragon/Steel is, in a sense, subsidized by needing to actively plan around its own STAB being commonly walled — a genuinely elite defensive typing rarely comes free on the offensive side as well.
Why Ground and Fighting Specifically Remain Uncovered
It's not an accident that Dragon/Steel's two weaknesses are Ground and Fighting rather than any other pairing — both are physical-category types with no type in the game that resists both of them simultaneously the way Steel resists so much of the rest of the chart, and Game Freak has generally avoided printing a typing that resists Ground, Fighting, and everything else at once because it would functionally have zero weaknesses, an outcome the design team treats as a hard boundary except for the rare pre-Fairy accident like Spiritomb. That design restraint is exactly why Dragon/Steel Pokémon universally lean on either raw physical bulk (Dialga, Archaludon's Stamina) or Speed control (Duraludon) to manage the two remaining weaknesses rather than typing alone ever fully solving the problem.