Chi-Yu in depth
The beads that shaped the fire
The design starts from a small fish, but its main feature is the curved beads that form its eyes. Paldea's story links them to the envy built up around valuable objects that caused conflicts. Chi-Yu does not wear those beads as an accessory: they are the essential part of the creature, while the body of fire forms around them. The result connects an aquatic animal with a fiery calamity without turning it into an ordinary fish.
The Japanese name, イーユイ, is read “Yīyú”. Its official romanisation is Chi-Yu. The name is linked to Chinese terms associated with the goldfish and jade, a combination that fits its silhouette and the beads representing the origin of its legend. The English category, “Ruinous Pokémon”, refers to Paldea's four ruinous treasures and not to a shared evolution.
A debut that changed its numbers
Chi-Yu appeared in the ninth generation, in Pokémon Scarlet and Pokémon Violet. It has no presence in earlier generations and no moves inherited from other games in the main series. Its playable story revolves around a sealed shrine and the stakes keeping the entrance closed, so the capture is kept separate from the usual journey through grass and caves.
Its base stats were adjusted through a game update. The distribution currently in use keeps the same total of 570: 55 HP, 80 Attack, 80 Defense, 135 Special Attack, 120 Special Defense and 100 Speed. The change affected its base figures, not its concept or its Ability.
The attacker of the ruins
Among the four ruinous treasures, Ting-Lu represents endurance and attrition, Chien-Pao focuses on physical damage and Wo-Chien stands out for its more defensive profile. Chi-Yu occupies the special end of the group. Its Special Attack of 135 is the figure that matters most, and Beads of Ruin makes opponents take even more special damage when they switch in against it.
In a normal playthrough, it works best when it comes in after forcing a switch or after another Pokémon removes entry hazards. Dark Pulse covers opponents that resist Fire, while Fire Blast and Overheat pressure targets that cannot withstand its Fire-type attacks. Nasty Plot is useful for punishing passive switches, although its low HP leaves little room to set up.
How it gets snuffed out
Its biggest limitation is its physical defence. A Ground-, Water-, Rock- or Fighting-type attack can remove it from the field if it does not come in with an advantage. It also struggles against Pokémon with high Special Defense, especially if they resist Fire and do not take enough damage from Dark Pulse. Its Speed of 100 lets it outspeed a broad part of the metagame, but it is not enough to stop fast attackers or priority from finishing it off.
In doubles battles, Beads of Ruin becomes more valuable because it lowers the Special Defense of both opponents and lets another special attacker take advantage of the same opening. In singles, its role is more direct: switch in, force a response and hit with power that rarely needs preparation. The imperfect accuracy of Overheat and Fire Blast introduces a risk that does not exist with Lava Plume, but the damage from its Fire-type moves explains why it remains a threat despite having few chances to switch in and out.