Ultimate Mode Miraidon is a large robotic reptilian Pokémon. Most of its body is violet in color, although its face, claws, abdomen, and tail are gray. Additionally, there are light blue accents on its shoulders and legs, the latter of which resemble jet engines when folded and allow it to float in the air. Its head has a dark purple casque, circular purple cheeks, two pairs of antennae, and black eyes. The eyes have a pixelated display; they usually show yellow-cyan pupils, although Miraidon can simulate blinking by changing the display pattern. Inside Miraidon's body is what appears to be purplish-yellow energy, with light blue streaks accenting it. This energy is mostly concentrated on its throat (forming a prominent circular growth), tail, and antennae (which can emit the energy in a manner similar to electricity).
Low-Power Mode Miraidon walks on all fours, with the jet engine-like legs unfolding. The antennae become light sliver along with the throat. The eyes are light blue. The other glowing parts of its body become violet. Miraidon assumes this form either when weakened or not battling.
Miraidon has the ability to change its form in order to facilitate travel. Drive Mode Miraidon can generate the energy in its tail and throat and turn them into wheel-like rings, which allow it to accelerate. Drive Mode Miraidon is capable of driving up cliffs. Aquatic Mode Miraidon is similar in appearance to Drive Mode and propels itself using both its rings and the jet engines on its legs. Glide Mode Miraidon moves its antennae in order to expand an energy membrane, allowing it to glide through the sky.
Miraidon was brought to the current era through a time machine created by Professor Turo but it is different from the other Paradox Pokémon. He was capable of only bringing two of them, and is also the one who coined Miraidon's name. According to the Violet Book, Miraidon is known as the Iron Serpent and is said to be much more ruthless and powerful than its ancestor Cyclizar. It is powerful enough to use its lightning to turn the land into ash.
While apparently accustomed to humans, Miraidon uses its power of insight and observation to carefully judge a person's character before it decides whether to join them or not. It has a calm and collected disposition, and it is very difficult for others to tell what it is thinking or feeling due to its robotic nature, with the only available hints presented in its eyes. In its Ultimate Mode, it keeps itself afloat to maintain an advantageous position that applies pressure to grounded opponents, and it anticipates their moves before striking at their weak points. It uses the electricity generated in its internal organs to charge its claws, fangs, and tail. One strike from its charged tail is said to knock out even the sturdiest foe.
Miraidon is the only known Pokémon capable of learning the move Electro Drift.
- Miraidon and Koraidon are the only Paradox Pokémon whose names follow regular Pokémon naming conventions.
- Additionally, they are the only Paradox Pokémon to each have their own unique Abilities.
- They are also the only Paradox Pokémon to not have different names in Spanish and Italian.
- Miraidon is the tallest Paradox Pokémon and the only future Paradox Pokémon to be larger than its regular counterpart, rather than smaller.
- Miraidon has the highest base Special Defense stat of all Electric-type Pokémon.
- Of all Pokémon, Miraidon and Koraidon have the highest number of forms that are obtainable in some capacity yet unusable in battle, as they each use three forms solely for travel and are obtained in their fourth ‘low-power’ forms, yet can only battle in their ‘high-power’ forms.
- Rotom has five forms that are unusable in battle (Pokédex, Phone, Bike, Rotomi, Drone), but Rotomi and Rotom Drone are completely unobtainable.
- The modes of Miraidon in Japanese and Korean use borrowed words from English, showing modernity, while the builds of Koraidon in the same languages use the native words from their respective language, showing tradition and the past.
Miraidon's appearance may be based on a robotic Chinese dragon and various lizards, such as the anole or the genera Sitana and Sarada — the latter two are collectively known as fan-throated lizards. Its robotic look might also be a reference to how futuristic cultures are often depicted with the overuse of machines and robots, as opposed to Koraidon's traditional look. Some elements of its design may be based on parts of various motorized vehicles, with its casque resembling a motorcycle windshield, its shoulders being similar to handlebars, its rear looking like the backrest of a vehicle seat, its throat and tail resembling wheels when active, and its legs resembling jet engines or exhaust pipes. Miraidon's ability to rearrange itself when changing between forms may be inspired by transforming robots.
Looking at its snake-like body and its Electric type, it possibly takes inspiration from el Cuélebre, a famous creature from the Spanish mythology, oftenly associated with the thunder.
Miraidon may be a combination of 未来 mirai (future), ライド raido (ride), dragon, don (Spanish for lord), and -don (common suffix in dinosaur names derived from the Ancient Greek word for tooth).
Its alternate name, Iron Serpent, is literally iron serpent.
Tetsuno'orochi, its alternate name in Japanese, can be taken literally as 鉄の大蛇 tetsu no orochi (iron serpent).