Transformation Magic: By using Soleil as a medium, Ida is temporarily able to harness the powers of a demon and transform using the negative feelings of a human. To do so, she must meet two requirements: First, there must be a human under intense stress and have high levels of fear radiating from them, and secondly, she must be in direct contact with both Soleil and the human that meets the previous requirement. If all all of these are met, then she will use the negative emotions from the human to take on a new form symbolizing that humans greatest fears. Neither Ida nor Soleil have any control over what the form will be, though.
Master Sword Fighter: Ida is extremely proficient at fighting with a sword due to her intense training to become a royal knight. She doesn't use a sword except for on Euria, but she has been shown to be able to defeat hordes of enemies by using her technique with her swords.
Master Hand-to-Hand Combatant: Due to said intense training, she has become a master hand-to-hand combatant on the chance that she cannot use her swords. She is shown to be very capable of disarming, or even killing, opponents quickly and efficiently empty-handed.
Enhanced Agility: She has incredible agility due to the royal knight training, using her lean body to its fullest capacity, shown in her easily being able to react to and dodge bullets and surprise attacks without any trouble.
Immense Durability: Even before she started her training, Ida has been incredibly hard to damage or knock off-balance, as even trying to draw blood takes a much greater force than should feasibly be necessary. Her skin can't be cut through with a knife and bullets bounce off of her without leaving even a scratch. Due to this, she takes on what would be fatal blows without batting an eye, using it to knock her opponent off-balance.
Immunity: Since she comes from another dimension, she is entirely immune to Earth's diseases and viruses, as they are much weaker than those back on Euria. Despite running herself ragged at times, she never catches a cold or fever, nor has she had any problems with allergies. She is also immune to most poisons and venom due to her royal knight training.
Pain Resistance: She has a very high tolerance for pain, never once going into shock from a particularly heavy blow. Only once has she shown pain, but she later told Midorin that it was only a ruse, in her words 'I didn't feel a thing, actually.'
Keen Intellect: She has been shown to be very capable of figuring out riddles and puzzles with great ease, even able to tell when others are lying just by analyzing smalls changes in their movements and speech patterns. She also has said that she does all of her planning during combat, showing she's able to formulate plans and strategies as she's fighting her opponent.