While most trainers evolve Onix into Steelix immediately, the unevolved form has a niche with Eviolite boosting its defenses. Electric moves can't touch it, which offsets the 6 weaknesses somewhat. Can go either physical or special depending on the set. Part of the Gen 1 roster.
The stat bars tell the story: Defense carries everything and Sp. Atk's dead weight. But this Rock Snake Pokemon still yields 1 Defense EV per fight on a medium-fast 1M XP curve.
This chain of immense stones resembles a giant serpent. Tremors shake the earth above as it burrows deep beneath the ground, feeding on boulders as it goes.
Onix Weakness
FragileOnix's Rock/Ground typing leaves it vulnerable to Water, Grass, Ice, Fighting, Ground, and Steel moves. Water and Grass hits land at 4x, so they're the biggest threat. It shrugs off Electric-type attacks completely. The Rock/Ground typing picks up 5 resistances to work with. Onix's physical bulk (base 160 Def) helps cushion physical weakness hits, but special attackers are the bigger threat.
To get Steelix from Onix, you need a trade. The evolution method matters here. The evolved forms gain up to 125 total stats over Onix.
How to Evolve
Breed Onix easily with 23 breeding partners from the Mineral egg group.
Onix doesn't rely on pure speed. Leftovers gives it passive recovery each turn to stay healthy, and Naive nature still pushes offense. Earthquake and the remaining moves keep the pressure on while max Sp. Atk and Speed EVs balance power and survivability.
Best Build
Legends: Arceus uses different battle mechanics.
Competitive build content is not applicable for this game. Select a main series game for builds.
A compact toolkit overall. The offense runs through Stone Edge and High Horsepower for Onix, with Normal and Steel coverage doing what it can. Don't expect versatility from this one.
Level-Up Moves
TM Moves
Egg Moves
Tutor Moves
Onix starts showing up in mid-game routes at decent spawn rates across 4 encounter spots. The list below is sorted so you can pick what fits your current progress without scrolling through everything.
Best Locations
Walking encounters at walking across 4 spots for Onix. Sorted by progression so you can see what's reachable at your current point in the game.
At 385 BST, Onix is firmly in pre-evolution territory. Evolve it into Steelix before bringing it to any serious fight.
Watch for Starmie (Water), Exeggutor (Grass), and Cloyster (Ice) when using Onix. They all hit it super-effectively with STAB. Starmie is the most dangerous since Water moves deal 4x damage. Fighting, Ground, and Steel-type attackers are also a problem. With 6 weakness types, most competitive teams carry at least one counter.
Onix evolves into Steelix while holding a Metal Coat. Onix is the base form of this evolutionary line.
Rock Head protects against recoil damage — that's the one you want on Onix. Weak Armor is the hidden ability. Niche, but it has its uses. Sturdy works too if your team needs something different.
Onix is a physical attacker with base 45 Attack. Enough bulk to take a hit or two, too. But the speed tells the real story — base 70 Speed is workable — faster than some, slower than many.
Onix appears in 21 games, including Yellow, Red & Blue, and Gold & Silver.
Present since Red & Blue, Onix appears in 21 games spanning 9 generations. Gen 1 originals like Onix have the longest track record of availability in the series.
- Gen IY
Yellow - Gen IRBDebut
Red & Blue - Gen IIGS
Gold & Silver - Gen IIC
Crystal - Gen IIIRS
Ruby & Sapphire - Gen IIIFRLG
FireRed & LeafGreen - Gen IIIE
Emerald - Gen IVPt
Platinum - Gen IVHGSS
HeartGold & SoulSilver - Gen IVDP
Diamond & Pearl - Gen VBW
Black & White - Gen VB2W2
Black 2 & White 2 - Gen VIXY
X & Y - Gen VIORAS
Omega Ruby & Alpha Sapphire - Gen VIIUSUM
Ultra Sun & Ultra Moon - Gen VIISM
Sun & Moon - Gen VIILGPE
Let's Go Pikachu & Eevee - Gen VIIISwSh
Sword & Shield - Gen VIIIPLA
Legends: Arceus - Gen VIIIBDSP
Brilliant Diamond & Shining Pearl - Gen IXSV
Scarlet & Violet - Gen IXLZA
Legends: Z-A