Magnemite in depth
A coil with one eye
Its Japanese name is コイル, read as “Coil”: a coil. It is the part found inside any electromagnet, and the design makes its origin obvious—the spherical body with two horseshoe magnets on the sides and a single eye in the center also brings classic flying-saucer imagery to mind. The English name Magnemite combines magnet with the suffix -mite, making it the small magnet of the family.
That reading supports the whole line. Magneton is a cluster of three, and Magnezone is what happens when that cluster enters a strong enough magnetic field. None of the three has limbs or a face in the usual sense, and all three behave like devices that happen to be alive.
Steel arrived in Gold and Silver
In the first generation, it was pure Electric. Steel was introduced in the second, and this line was one of those given the type retroactively, a change that rearranged everything it could do. It gained an immunity to Poison and a battery of resistances it had not had before; in exchange, its weakness to Ground went from double to quadruple, and two new holes appeared against Fire and Fighting. Few species have changed their behavior so much without having their stats touched.
Sturdy also changed along the way. During the first four generations, it only worked against one-hit knockout moves; from the fifth onward, it became a permanent Focus Sash and guaranteed survival with 1 HP from full HP. For a Pokémon with 25 HP, that turned an almost decorative ability into the reason to use it.
Similarities that are not relatives
Klink takes a comparable approach from another angle: gears instead of magnets, pure Steel instead of a dual type, and a line that also evolves by adding pieces. The practical difference is that Klink solves battles physically while Magnemite does it specially, and that only one of them carries the four-times weakness to Ground.
How to use it when it only has 25 HP
The level-up movepool sets the pace. It does not get a damaging Steel-type move—Flash Cannon—until level 32, and before that it brings status and disruption: Supersonic at 4, Thunder Wave at 8, Screech at 24, Magnet Rise at 28. The sensible way to play it early is as a nuisance, not an attacker: paralyze, lower Special Defense with Screech and let something else do the hitting.
Gyro Ball, which it learns at level 16, works in the opposite way to almost everything else: the slower its user is compared with its target, the more power it has. With 45 Speed, it is one of the few cases where being slow pays off, although against equally slow opponents it amounts to nothing.
And there is a detail that often goes unnoticed: it gives 1 Special Attack EV when defeated, and it appears in groups around electrical areas. To train that particular stat, finding a tower with several of them nearby gets the job done without looking anywhere else.