The shadow turns invisible. Phantom Sylus stalks you, executes you below 50% HP, and demands perfect spatial awareness.
The Core Insight: Phantom Sylus is an assassin boss. It spends most of the fight invisible, emerging only to strike. Unlike Phantom Xavier (which adapts to your inputs), Phantom Sylus follows a strict patrol-and-ambush cycle. The fight is about prediction: learn where it will emerge, pre-position, and punish the reveal.
Phantom Sylus is a Dark-element humanoid boss that uses stealth and execute mechanics. It is the second Phantom boss encountered in Abyss and Orbit progression. The fight alternates between "Hunt" phases (boss invisible, stalking you) and "Strike" phases (boss visible, attacking). Managing this cycle is the key to victory.
Tell: A faint shimmer in the air + audio cue (whisper). The phantom is invisible and preparing a strike.
Behavior: If your HP is below 50%, the phantom deals 500% ATK. Above 50%, deals 250% ATK. The strike is always from behind.
Dodge: The moment you hear the whisper, dodge forward. The phantom always strikes from behind. Forward dodge = invulnerability frames through the attack.
Counter: After the strike, the phantom is briefly visible (1s). This is your only punish window during Hunt phases. Xavier's Stellar Burst (with Sigils) can hit before it vanishes.
Tell: Phantom Sylus crouches and dissolves into shadow. 0.5s cast.
Behavior: Goes invisible for 5-8 seconds. During invisibility, it moves to a new position and prepares Shadow Strike. The phantom leaves a faint shadow trail on the ground 閳?this is the only visual cue for its position.
Strategy: Watch the ground shadow trail. The phantom moves in a predictable pattern: always toward the farthest corner from you. Pre-position near where the trail ends.
Tell: Phantom Sylus becomes fully visible, raises both arms, and dark energy pulses outward. 2s cast.
Behavior: Deals 600% ATK to all enemies. If any enemy is below 30% HP, they take 900% ATK instead. Massive arena-wide damage.
Dodge: This attack is arena-wide with no safe zone. Use Zayne's Glacial Barrier or iframe through with a well-timed dodge at 1.5s (the damage frame).
Counter: After Dark Harvest, the phantom is staggered for 3s. Full burst window. Xavier's Light's Judgment deals +30% damage (Light weakness).
Behavior: Phantom Sylus becomes visible and performs a 5-hit combo: 3 quick slashes 閳?0.5s pause 閳?2 wide slashes. Each hit deals 120% ATK. The final hit has a 180-degree arc.
Dodge: Dodge pattern: side 閳?side 閳?side 閳?wait 閳?side 閳?toward. The pause before the final two slashes is your dodge reset window.
Counter: After the last slash, the phantom is exhausted for 1.5s. Zayne's Frost Bolt can freeze it during the pause between hits.
Phase 1 (100%-60%): Hunt-Strike cycle only. Phantom uses Veil Step 閳?Shadow Strike repeatedly. No ultimate. Predictable timing: 5s invisible 閳?strike 閳?3s visible 閳?5s invisible.
Phase 2 (60%-30%): Gains Dark Harvest (ultimate). Uses it once every 40s. Hunt phase speed increases (3-5s invisible instead of 5-8s). The phantom may chain two Shadow Strikes in a row before becoming visible.
Phase 3 (30%-0%) 閳?Enrage: Phantom is permanently visible. Uses Shadow Dance combo repeatedly. May cast Dark Harvest while comboing. All attacks deal +35% damage. The invisibility mechanic is gone 閳?replaced by relentless combos.
Why: Light element is the boss's weakness (+30% damage). Xavier's Stellar Burst can hit the phantom during its brief post-strike visibility window. Crystal Resonance with Zayne provides defense shred.
Memory: Stellar Contract (S-tier). ATK buff on skill use maximises burst during the phantom's visible phases.
Why: Freeze is invaluable against Phantom Sylus. A frozen phantom cannot go invisible, cannot Shadow Strike, and cannot use Dark Harvest. Freeze lock during Phase 2 prevents the ultimate entirely. Glacial Barrier saves you from execute-range Dark Harvest.
Memory: Permafrost Covenant (A-tier). Extended freeze duration.
Tip #1 閳?Use Walls: Phantom Sylus always moves to the farthest corner during invisibility. Position yourself near a wall 閳?the phantom will emerge in the opposite corner, giving you maximum reaction time.
Tip #2 閳?Count the Strikes: Phase 1: always 1 strike per invisibility. Phase 2: can be 1 or 2 strikes. Wait 2 seconds after the first strike before committing to attacks 閳?a second strike may follow.
Tip #3 閳?Heal Before 50% in Phase 2: Dark Harvest deals 900% ATK to targets below 30% HP. If you're at 35% HP when the phantom starts casting, use a heal or Zayne's shield immediately. Getting caught below 30% is almost certain death.
Tip #4 閳?Phase 3 is a DPS Race: Once enrage starts, the phantom stops going invisible. This means constant damage uptime. Use all cooldowns. The fight becomes a straightforward DPS check 閳?survive the combos and burn the boss.
Mistake #1: Panic-dodging on audio cue. The whisper triggers a natural panic response. But dodging too early means the phantom delays its strike and hits you after your dodge ends. Wait for the whisper to finish, then dodge.
Mistake #2: Not watching the shadow trail. The ground shadow trail is the only reliable indicator of the phantom's position during invisibility. Many players ignore it and rely on guesswork. Watch the ground 閳?not the air.
Mistake #3: Letting HP drop below 50% in Phase 1. Shadow Strike at 500% ATK is devastating. Keep your HP above 60% at all times during Hunt phases. If you're low, don't chase damage 閳?focus on survival until you can heal.
Mistake #4: Not bringing Light element. Phantom Sylus resists Dark (-20%). Bringing Sylus against Phantom Sylus is a 50% damage disadvantage. Xavier (Light) deals +30% 閳?the correct element choice is non-negotiable.
The Bottom Line: Phantom Sylus is a predator-prey fight. You are the prey. The boss is invisible most of the time, emerging only to execute you. Watch the shadow trail. Dodge forward on the whisper. Freeze with Zayne to cancel invisibility. Keep HP above 60%. And in Phase 3, drop the defensive play and burn the boss before it burns you. Bring Xavier, watch the ground, and survive.