The 10th Edition Codex: Aeldari introduces significant updates to the faction’s rules, units, and strategies, encompassing Asuryani, Harlequins, and Ynnari.

Army Rule – Battle Focus:
Replacing Strands of Fate, the new Battle Focus rule provides a pool of tokens each Battle Round (2/4/6 for Incursion, Strike Force, and Onslaught, respectively). These tokens can be expended to activate one of six mobility maneuvers for units with the Battle Focus ability:
	•	Swift as the Wind: Adds 2” to a unit’s Move characteristic during Normal, Advance, or Fall Back moves.
	•	Flitting Shadows: Prevents a unit from being targeted by Overwatch after making a move or being set up.
	•	Star Engines: Grants Vehicles an additional d6+1” to their Move characteristic during a Normal Move.
	•	Sudden Strike: Provides 6” Pile-in and Consolidation moves when a unit is selected to fight.
	•	Opportunity Seized: Allows a unit to make a Normal Move of d6+1” after an enemy unit falls back from engagement.
	•	Fade Back: Enables a unit to make a Normal Move of d6+1” after being hit by an enemy’s shooting attack.

This rule enhances the Aeldari’s agility and flexibility, emphasizing their strategic mobility on the battlefield.

Detachments:
The codex offers eight distinct detachments, each focusing on specific sub-factions or themes within the Aeldari:
	•	Warhost Detachment: Emphasizes traditional Craftworld units, providing an additional Battle Focus token and bonuses to movement-related maneuvers.
	•	Windrider Host: Centers on jetbike units, allowing Windriders as Battleline and offering enhanced mobility through redeployment abilities.
	•	Aspect Host: Focuses on Aspect Warriors, granting flexible re-rolls to hit or wound rolls, enhancing their combat effectiveness.
	•	Seer Council: Highlights psyker units, augmenting their psychic capabilities and support roles.
	•	Spirit Conclave: Concentrates on Wraith constructs, bolstering their resilience and combat prowess.
	•	Guardian Battlehost: Enhances Guardian units, improving their battlefield roles and effectiveness.
	•	Ghosts of the Webway: Dedicated to Harlequin forces, focusing on their unique mobility and combat tactics.
	•	Devoted of Ynnead: Caters to Ynnari units, integrating Asuryani, Drukhari, and Harlequin elements with unique mechanics.

Key Unit Updates:
	•	Autarchs: Now capable of leading Aspect Warriors that match their movement type, increasing strategic options.
	•	Swooping Hawks: The “uppy-downy” ability is now exclusive to Baharroth. Hawks gain a new ability to inflict mortal wounds after moving within 8” of a visible enemy.
	•	Shining Spears: Receive significant enhancements, making them formidable against tanks and elite infantry.
	•	Wraithlords: Benefit from Psychic Guidance, improving ballistic and weapon skill, and the Fated Hero ability, allowing re-rolls against selected keywords.
	•	Heavy Weapons: Shuriken Cannons now have Lethal Hits; Scatter Lasers gain Sustained Hits.
	•	Support Platforms: Vibro Cannons increase in strength and damage with consecutive hits; Shadow Weavers introduce the Monofilament Snare, causing mortal wounds during enemy movement.
	•	Windriders: Experience a reduction in armor save but gain a 6+ invulnerable save. Their Swift Demise ability now offers re-rolls against all targets, with full re-rolls against the nearest enemy.
	•	War Walkers: Return to a 5+ invulnerable save, losing the -1 Wound ability. They now increase the AP of attacks against units they’ve hit, enhancing army-wide effectiveness.
	•	Rangers and Shroud Runners: Rangers remain largely unchanged, while Shroud Runners see improvements in ballistic skill and gain Sustained Hits on their Scatter Lasers. Their new ability allows them to grant army-wide Ignore Cover to units they’ve hit.
	•	Corsairs: Experience minor weapon adjustments, with some profiles receiving increased damage or armor penetration.

Grav Tanks:
	•	Wave Serpent: Offers increased durability with an extra wound and a 5+ invulnerable save. Its Wave Serpent Shield reduces the effectiveness of high-strength attacks.
	•	Falcon: Provides heavy weaponry and offensive buffs, with a transport capacity of six. It can Deep Strike, offering flexibility in deployment.

Harlequin Updates:
	•	Harlequin infantry gain the Flip Belt ability, allowing them to ignore vertical movement during various moves. The Choreographer of War no longer provides Devastating Wounds but enhances unit positioning during the Fight Phase.
	•	Troupes receive the Dance of Death ability, offering options to re-roll hits, add to wound rolls, or subtract from enemy hit rolls in the Fight Phase.

Overall Assessment:
The codex introduces a range of specialized units and abilities, allowing players to assemble highly effective and thematic Aeldari armies. While the loss of Fate Dice reduces some reliability, the new Battle Focus rule and detachment-specific abilities offer compensatory advantages. The codex provides a diverse toolkit, enabling various playstyles and strategies for Aeldari commanders.