Dialga is a dark blue sauropod-like Pokémon with some gray metallic portions, such as its chestplate, which has a diamond in the center. It also has various light blue stripes. It has a fin-like structure on its back and a crest on its head, resembling a dinosaur. Dialga also has two horns on top of its head, two fang-like horns around its mouth, and three spines on the back of its neck. It has three claws on each foot of the same metallic looks as its chestplate. Faint cracks exist across its body. The wing-like structure on its back can be used to focus the flow of time, as seen in Explorers of Time, Darkness, and Sky.
Dialga can warp time by either speeding it up, slowing it down, or stopping it altogether. As Dialga primarily resides in a different dimension, its behavior is nearly impossible to study. It has been shown to be very protective of its home. It also tends to have violent conflicts with its counterpart, Palkia. Dialga is the only known Pokémon that can learn Roar of Time.
Dialga's final movie appearance was in Arceus and the Jewel of Life, where it was shown for the first time with both the other members of its trio. After being called by Sheena to stop a spatial distortion, it briefly fought with Giratina once more. Later, it returned to help Palkia and Giratina fight Arceus. After being injured, it sent Sheena, Ash, and his friends back in time to fix Arceus's betrayal.
Dialga appeared in The Battle Finale of Legend!, where it and Palkia were summoned by Cyrus on the Spear Pillar. They were put under his control through the use of the Red Chain and were tasked by him to open a portal to another dimension, wanting a world of his own. After the Red Chain's destruction and Cyrus's exit, Dialga and Palkia rampaged, creating a danger for Sinnoh. However, the two were calmed down and sent away with the help of the lake guardians.
Dialga appeared in The New World along with Palkia. Both of them were captured at Spear Pillar by Cyrus, who intended to use them to destroy the world and create a new one. Along with Palkia, it was freed by Giratina before they could help Cyrus succeed in his goal.
In the twelfth movie manga adaptation, Dialga, along with the other members of its trio, was summoned by Sheena to help Ash and his friends. Dialga, Palkia, and Giratina battled Arceus and it soon puts Sheena and the others in the past to uncover the act of betrayal Sheena's ancestor committed.
Dialga, along with Palkia, was summoned by Cyrus in the Diamond & Pearl chapter in order to create a new world. Cyrus used the Red Chains to force Dialga and Palkia to fight each other in order to distort time and space and create a portal that would swallow the existing world. Diamond, Pearl and Platinum worked together with their Pokémon to free Dialga and Palkia from their controlled states. It first appeared in Creeping Away from Cradily.
Later on, an accident with handling Charon's machine caused Dialga, Palkia and Cyrus to be dragged into the portal before it closed completely. In the Platinum chapter, it was revealed that Giratina imprisoned both Dialga and Palkia in the Distortion World before setting off into the current dimension to wreak havoc. Soon, Cyrus and Diamond met in the Distortion World, and agreed to free Dialga and Palkia using their Pokémon. Dialga and Palkia later resumed their struggle against Giratina in the Distortion World. When Charon decided to escape from the Distortion World on Giratina, Diamond got on Dialga and chased after him. Giratina was eventually defeated, with Dialga and Palkia forcing it back into the Distortion World for good, before both returned to the Spear Pillar.
Dialga appears as a stage Pokémon along with Palkia, Cresselia, and the lake guardians on the stage Spear Pillar. It affects the stage much differently than that of its counterpart, such as slowing down time, and even going off its post to attack the players in the middle. It can also distort the stage, like Palkia, but only slightly and not as extreme, as well as shoot beams from various locations.
A Temporal Pokémon. This legendary Pokémon is talked about as a deity in fables passed down through generations in the Sinnoh region. Identifiable by the diamondlike crystal in the center of its chest, Dialga is said to have set time in motion at the moment of its birth. Its fearsome Roar of Time attack is so powerful that it must refrain from attacking on the next turn. It is Diamond's mascot.
The concept of time has always been one of the world's great mysteries, but Dialga might hold the answer. Legend has it that Dialga's birth caused time to begin moving! It's no surprise that the people of Sinnoh see this Pokémon as a deity. If you're ever running late, maybe you could ask Dialga to do you a favour and turn back the clock.
Pokémon Mystery Dungeon: Explorers of Time, Darkness& Sky: Dialga appears in the main storyline, but mostly as Primal Dialga. In the future, because of the collapse of the Temporal Tower, Dialga has lost control of itself and has entered a state of self-preservation, keeping time frozen and refusing to let it flow properly. When the player and partner return from the future and arrive at the collapsing Tower, they must beat almost-Primal Dialga in battle and restore the Tower. After putting some sense into it, Dialga is so grateful that it revives the player (who was erased from existence). After going back to Dialga at the top of Temporal Tower, it decides that the player wants a rematch. Once defeated, Dialga joins the player's team. In the Sky-only Special Episode In the Future of Darkness, after the final battle between Primal Dialga and the trio of Grovyle, Dusknoir and Celebi, all of them start to disappear due to the past finally being changed by the player, but are saved by an implied higher being than Dialga, who also restores Dialga to its normal state.
Pokémon Ranger: Shadows of Almia: Dialga appears as a bonus boss during one of the Ranger Net extra missions. Dialga was injured from a battle with Palkia and entered Almia Castle to recover. It caused a time distortion due to its wounds and sent the main character and Wendy back in time to before the events of the game started by using Roar of Time.
Pokémon Ranger: Guardian Signs: Dialga appears in the optional Ranger Net extra mission Pledge to Arceus. It must be captured along with its counterparts Palkia and Giratina in the Sky Fortress to access Arceus.
This Pokémon was unavailable prior to Generation IV.
The spikes on Dialga's back, at a certain point of view, look similar to a time gear. In the anime, when Dialga uses Roar of Time, the spine extends and the five spikes become thinner and more pronounced.
Dialga is the only Legendary Pokémon to have a role in four different movies.
According to Junichi Masuda's blog, the Spanish translation team suggested changing the name Dialga because of its similarity to the word alga, seaweed.
Dialga, along with Palkia, may be based on the Shinto legend of Izanami and Izanagi, who are said to have created one island with a spear, erected a pillar on it, and from there created the islands of Japan. Appearance-wise, Dialga seems to be based on short-necked sauropod dinosaurs such as Camarasaurus or Brachytrachelopan. Its type is Steel possibly due to the hardness of diamonds, the fact that metal is known to last long periods of time, or the fact that most parts of a clock are made of metal, such as the gears. It may also be because diamonds are compressed carbon, and steel is an alloy from iron and carbon. Its turquoise pattern on its body is vaguely reminiscent to clock hands, where the ends of the "clock hands" are diamond-shaped.
Dialga is derived from diamond. Ga may be a corruption of gon from dragon. It may also involve dia (Spanish for day, referring to a unit of time) or dial (as in sundial, an instrument used to tell time using shadows on a clock face).
In other languages
Derived from ダイヤモンド diamond. Ga may be a corruption of gon from dragon. May also involve dia (Spanish for day, referring to a unit of time) or dial (as in sundial, an instrument used to tell time using shadows on a clock face).