Changes

* The Onix line is the only multi-stage evolutionary family which can be completely acquired with [[in-game trade]]s. However, this is only possible in {{game|HeartGold and SoulSilver|s}}, in which the player can trade {{p|Bellsprout}} for Onix in [[Violet City]], and any Pokémon for Steelix in [[Olivine City]].

* The Onix line is the only multi-stage evolutionary family which can be completely acquired with [[in-game trade]]s. However, this is only possible in {{game|HeartGold and SoulSilver|s}}, in which the player can trade {{p|Bellsprout}} for Onix in [[Violet City]], and any Pokémon for Steelix in [[Olivine City]].

* The [[Lagging Tail]] [[held item]] resembles the end of Onix's tail.

* The [[Lagging Tail]] [[held item]] resembles the end of Onix's tail.

* Among all unevolved Pokémon, Onix;

* Among all unevolved Pokémon, Onix:

** has the highest {{stat|Defense}} stat,

** has the highest {{stat|Defense}} stat.

** is the [[List of Pokémon by weight|heaviest]],

** is the [[List of Pokémon by weight|heaviest]].

** and is the [[List of Pokémon by height|tallest]] - and the only [[Gigantic Pokémon]] that can evolve.

** is the [[List of Pokémon by height|tallest]].

* Onix is the only [[Gigantic Pokémon]] that can evolve.

===Origin===

===Origin===