Syd has teal hair with several strands that reach down his neck, teal eyebrows and pink eyes. His casual outfit consist of a white sleeveless tabard with blue bracers and blue boots. He also wears a blue cloak around his shoulders and a leather belt.
This casual attire is replaced by a blue outfit with sleeves when he wears his God Robe.
Syd is a rather arrogant man who thinks himself rather invincible with his powers, challenging the might of the Gold Saints by attacking Aldebaran by surprise. He also underestimates the Bronze Saints who have recently achieved victory against the Gold Saints.
House of Taurus
Syd arrives at the House, wrapping the entire House in ice which surprises Aldebaran. By the time he turns, Syd lands one blow against Aldebaran, which the Gold Saint barely evade before Syd lands several more attacks at the Gold Saint. However, as he lands the final blow, unknown to Aldebaran, Bud strikes from behind and Aldebaran is defeated.
Seiya and Shun
Arriving later at Saori's mansion, Syd confronts Athena, Tatsumi, Kiki and the Bronze Saints accompanying her. As they charge at him after he announces he has come from Asgard to kill Athena, he easily defeats them before he proceeds to kill Athena.
However, before he can land the killing blow, Shun's chains grab Syd's hand before Seiya launches a surprise kick to the God Warrior's face. Facing the two Bronze Saints who have received new Cloths after the battle of the Sanctuary, Syd easily surpasses Seiya's attack with his unimaginable speed and "Viking Tiger Claw" attack, leaving several frozen marks on Seiya's body.
Facing Shun next, he is impressed by the Bronze Saint's chains which are able to follow every single trail of his until he gains the advantage by using the sun as cover, striking Shun down with the same technique. Preparing to finish of Shun with another blast, he is surprised as Ikki arrives with his new Cloth as well and attempts to fight the God Warrior.
However, Seiya intervenes, stating that he will settle the score from earlier. Underestimating the Bronze Saint, Syd block his "Ryu Sei Ken" until Seiya's Cosmo increase, ripping apart the God Warrior's cape and wounding him. Impressed by Seiya's increasing Cosmo, Syd stands up and states that he should not underestimate the God Warriors of Asgard. Before they can resume their fight, Athena intervenes along with Shiryu and Hyoga in their new Cloths.
Realizing that the only way for him to kill Athena is if he defeats the five Bronze Saints defending her, Syd taunts Seiya before retreating.
When Shun arrives at the Valhalla Palace shortly after Alberich's defeat, Syd greets the Andromeda before they continue their battle where Syd gains the upper hand easily. Viciously attacking the Bronze Saint with his "Viking Tiger Claw", Syd is suddenly interrupted as Seiya and Hyoga arrive as well. Preparing to settle his score with Seiya from the last time, he instead attempts to prevent Seiya and Hyoga from passing through as Shun insist he will handle him.
As they pass through, Syd and Shun once more clash and Shun is left at the God Warrior's mercy once again. Annoyed at Shun's refusal to stand down, Syd uses his "Blue Impulse" which grievously injure Shun and damages his Cloth slightly before encasing him in ice. However, he is shocked as Shun stand up after taking his strongest technique.
Watching Shun remove his Cloth, Syd is horrified as the coldness in the Palace disappear and Shun gains the upper hand with his "Nebula Stream", immobilizing Syd. Preparing to finish of Shun quickly, Syd once more attack with his "Blue Impulse". However, Shun unleash his "Nebula Storm" which seemingly kills Syd.
However, he is still alive, although just barely, as he attempts to restrain Ikki from behind after his fight against Bud. Urging his twin brother to attack even though he will die himself from the impact, Syd laments that Bud is unable to perform his request, and dies shortly after of his wounds.
As Shun states, Syd's Cosmo may be equal or even stronger than that of the Gold Saints, allowing Syd to unleash blows at the speed of light. He does prove his might when he easily defeats Aldebaran, though it is later revealed that his twin brother Bud attacked from behind.
Viking Tiger Claw: Syd's fingernails extend to claws, in which he throws billions of sharp needles at the speed of light at his opponent, leaving small frozen marks on their bodies.
Blue Impulse: Syd's strongest technique. Gathering large mountains of ice behind him which burst, he emits an atom-like ball of energy from his Odin Sapphire which is so powerful that Shun's new Cloth reborn by the blood of the Gold Saints receives small cracks.
Syd wears the Mizar God Robe, one of the seven God Robes hidden in Asgard. Resembling a smilodon tiger with large fangs, the Robe has a powerful color of both dark green and a lighter green, with the eyes on his helmet being red. He also wears a white and red fabric cape around his shoulders.