I've been looking for this, but since I can't seem to find any threads/places listing what Thordama morphs do, unless you look at the morph description, I'm just going to make one.

Morphs: [Note that I'm using gene names for some of the abilities, you can look them up here,. Also, Grade 2/3 has everything that is lower: e.g Grade 3 Harvester has +30% Resource Find, Double Inscisors, and Steel Muscles -- too lazy to type them again)

Worker:

Artisan ability & Pheromones

Harvester: (Squad of Harvesters give you the Locust ability)

-- Negative Genes do not give you negative maneuvers on the battlefield.

Grade 1: Resource find (Island) +30%,

Grade 2: Double Inscisors,

Grade 3: Steel Muscle

Scout:

-- You have Sneak Attack and an additional Move manuever on the battlefield

Grade 1: Silent Pace, Sense of Direction

Grade 2: Scout, Watchman

Grade 3: Gracefulness

Defender:

-- Addition Defense maneuver

Grade 1: Steel Bones

Grade 2: Hitpoint is increased by 25%

Grade 3:  Magic Mirror, Plates

Warrior: (Squad of warriors gives the Stinking Cloud ability.)

-- Additional Attack maneuver

Grade 1: Sharp Claws, +10% Critical Strike

Grade 2: Poison Claws

Grade 3: Stench

Note: When it says additonal X maneuver, it means you get that maneuver early, e.g you get the 2nd one w/o having to the stat requirement.

I had noticed a spike in questions relating how to breed a Thordama morph, during the Autumn Event, so I'll try to explain it here. (I'll try to insert some pictures once I breed a new Thordama, and figure out how to do that.)

Anyways, here is the step by step guide:

1. Get a male and female thordama. [Plus an extra 1 or 2 if you're looking to get a higher grade.]

2. Complete the task for the Pheromone you want, on the male (and extras). [You can see the task on the lower right of the pet's profile.

3. Place the Thordamas in the same group

4. Breed the female with the male.

5. Go to the female's profile page, and something new will appear (forgot what it was labels as) -- this is where you select what morph you want, as well as select the provider of the pheromone {Remember that Thordamas can only ever produce one of each pheromone.}

PS. As you can see from the post above, Thordamas morphs can go up to Grade 3, and in order to get a Grade 3, you'll need to select 3 thordamas at Step 5.

The new box is called Use Pheromones, under Autobattle Settings. Nice and obvious. :)