They are first deployed in late June (mid-August on Legend) on either pure Chryssalid pods or as support troops for a Berserker.
The Chryssalid is a swift four-legged alien with terrifying melee capabilities. Evolved from the previous unit in XCOM: Enemy Unknown, this new creature is an enhanced, more deadly variant of the original. The Chryssalid is now much more visually imposing and physically dangerous, with spines, talons and razor-like skin. Its four insectoid legs allow it to burrow underground and hide from sight as well as leap extraordinary heights and move with frightening speed.
Much like its predecessor favoring Terror missions, the Chryssalid is most frequently seen on Retaliation missions. Its high mobility and metamorphosing poison make it extremely efficient at moving swiftly around the battlefield and killing civilians.
All Chryssalid melee attacks will cause poison. Organic units killed by poison will become a cocoon. If the cocoon is not destroyed during the gestation period, three new Chryssalids will emerge. Chryssalids have also gained the ability to burrow underground and lie in wait to ambush unsuspecting targets.
There are two types of encounters when meeting with Chryssalids:
- Packs: these Chryssalids move in groups and act like most other enemy pods, deploying when they spot you.
- Burrower: burrowers are lone Chryssalids that can emerge from the ground, move and attack even if it is still your turn. Be aware that you are not safe even when you are taking actions.
- Scanning Protocol of the Specialist class will force the Chryssalid to emerge for the turn it is active.
- Specialist's Aid Protocol can be used on the scouting unit to reduce the chance of being hit by the burrowed Chryssalids.
- It is useful, when advancing in a mission where burrowed Chryssalids are suspected to be present, to move a "point guard" unit last and place other units behind them on Overwatch first, so as to cover the point guard. Follow up on the next turn by advancing the squad up to the point guard's new location, putting them on Overwatch again, then moving the point guard up once more.
- A Ranger with Bladestorm is extremely useful against overeager Chryssalids. The attack will usually not kill a Chryssalid with one hit, but if other Overwatch shots connect it is more than useful for finishing it off.
- While burning, Chryssalids cannot use their melee attack, effectively rendering them useless. Using incendiary grenades/bombs or dragon rounds is recommended.
- A Bladestorm Ranger with a Fusion Blade is very useful combination.
- As a last line of defense, Hellweave ensures any Chryssalid that lands an attack will be set ablaze.
- A Hazmat Vest confers immunity to poison, leaving only the melee damage. Psi Operatives with the Fortress skill are unaffected by poison as well.
- If a humanoid enemy is killed with a mind controlled Chryssalid, all Chryssalids emerging from the cocoon will still be hostile.
- In multiplayer you are able to spawn Chryssalids from the pod the first turn after the host is killed. Chryssalids are spawned one at a time, and you appear to have to wait for a while before three can be spawned. Spawning too quickly will only allow two total: this is known to be a glitch.
- Chryssalid poison does not expire and must be cured with a medikit or a medic-oriented Specialist's abilities. However, unlike being set on fire, it does not restrict your actions.
- Poison immunity from a medikit does not apply to Chryssalid poison.
- When a human is carrying Chryssalid eggs and is affected by a Gatekeeper, it will duplicate the human, one psi zombie and one egg carrier.
- Chryssalid poison can also be countered by evacuating the afflicted soldier.