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TheLastDivinity This article, Bog Chrysalis, is content only available with The Last Divinity, DLC.

Bog Chrysalis is a Banner Unit of the Wurmkin Clan Wurmkin.png. It has Shell 5, and summons 2 Bog Flies when all Shell is removed. These bog flies inherit all upgrades and stat changes applied to the original egg.


The Wurmkin do not breed. At least, not anymore. Upon their decision to remain hidden, they created thousands of eggs, ready to hatch on command, eschewing the need for further reproduction. What a shame.


Bog Chrysalis is an egg that hatches into two Bog Flies after it hatches that inherit the egg's stat changes and upgrades, effectively acting as two units in one. Since all upgrades and stat changes are applied to both bog flies after the egg hatches, their value is effectively doubled.

However, the above relies on one being able to actually hatch the egg. Thus, one needs to be able to remove 5 Shell while protecting the egg with 1Health at base. Hardened Hull helps directly in both tasks.

Bog Chrysalis fits very well behind Infector Spine Chief. The Infector's Strike ability generates charged echoes which not only helps to hatch the egg, but after that will also power up the Bog Flies' attack. Especially against the boss's relentless, if the chief can survive a few turns, the flies' attack will be supercharged to a very high level.

Bog Chrysalis also works very well behind Corruptor Spine Chief. The Hatched Bog Flies represent 2 more attacks for the Chief to buff, and upgrading the Chrysalis' with Multstrike increases the attacks to 4, since the upgrade applies to both hatched units. Since the Bog Flies also scale with echoes themselves, they can scale their attacks to game winning levels.

Suggested Upgrades[]

Upgrade Description
Upgrade Unit Heartstone.png Heartstone helps prevent the egg dying early, as it has 1Health.
Upgrade Unit Frenzystone.png Since upgrades apply to both hatched units, Frenzystone ends up representing 2 more strikes instead of 1, essentially applying twice.
Upgrade Unit Echo Stone.png Echo Stone gives both the egg and the flies an extra +3Attack per Echo which is doubly effective after the egg hatches.
Upgrade Unit Immortalstone.png By giving the unit Endless, you can now replay the egg after it hatches, allowing you to summon more Bog flies with just one egg. This is especially effective with Hardened Hull, reducing the echoes needed substantially.

Pacts & Unit Essence (The Last Divinity (DLC) only)[]

Since all upgrades, including Unit Essences, pass down to the hatched units, Infusions with Summon effects happen 3 times total after the egg is hatched, and scaling effects happen to 2 units after hatching. Since Hatch effects kill the egg unit, Extinguish also trigger when the Chrysalis hatches. However, do note that Status Effects applied after the Chrysalis is placed do not pass down, and anything including stat changes on the hatched units do not affect the egg itself.

For example, Bounty Stalker's essence's effect only applies its permanent Attack when the Egg dies or Hatches, and not when the Bog Flies die. (The Extinguish ability on the flies fizzles to no benefit, they being Cardless units.) However, the bog flies still benefit from the permanent attack when the egg hatches.

For another example, Welder Helper's essence on Bog Chrysalis allows the Summon ability to be triggered by both the egg and each fly, adding 10 Armor to the floor when the egg is summoned, and adding 20 more Armor to the floor when the egg hatches. However, the 10 Armor applied to the egg itself is not passed down. (The hatched flies get their own 10 Armor from inheriting the essence, so they end up with 30 Armor each.)


See: Version History

Version Changes
2.0.0 Added Bog Chrysalis.