Fusion Skills

Fusion skills bring a minor but sensible advantage to your titans, sufficient to upend contested battles.

They are randomly created and upgraded with elemental catalyst and primal catalyst. They are bound to your totem and cannot be removed or replaced.

Copies of the same skill do not stack. At best you will refresh the duration of the buff.

Elemental Skills

Last FlashLast FlashIce AgeIce AgeWrath of the DepthsWrath of the DepthsFlame DanceFlame DanceThe Depths WhisperThe Depths WhisperMurmur of the CragsMurmur of the Crags

Primal Skills

Pulse of the AncientsPulse of the AncientsPrimal ZealPrimal ZealEcho AegisEcho AegisTriple CycleTriple CycleCall of ElementsCall of Elements

Optimal Strategy

Here is how many catalysts to spend at a time to maximize your odds.
It may be beneficial to stop at rank 4 and use the bad luck protection for the last upgrade.

When you have no skill yet Spend 10 catalysts to gain any random skill - accept the temporary result
When you have a skill already Spend 100 catalysts at a time

Average Cost to Reach Rank 5

Assuming you follow the optimal strategy described above. Hope you like casinos... :(

Rank 1 → 5 2146 catalysts (100 at a time)
Rank 2 → 5 2143 catalysts (100 at a time)
Rank 3 → 5 2126 catalysts (100 at a time)
Rank 4 → 5 2024 catalysts (100 at a time)

Average Cost to Reach Rank 4

Rank 1 → 4 867 catalysts (100 at a time)
Rank 2 → 4 864 catalysts (100 at a time)
Rank 3 → 4 805 catalysts (100 at a time)

Replacing a rank V skill

switching fusion skills is ridiculously cheap once at rank V

Once you reach rank V, switching becomes cheap: you have 19.3% chance of getting another rank V by spending 10 catalysts, and 23.1% by spending 100.

Therefore the optimal strategy is to spend 10 at a time despite the risk of getting a random skill - in which case you just refuse it. Here are the average costs:

Elemental Skill (10 at a time) 155 catalysts
Primal Skill (10 at a time) 135 catalysts

Crystallized Might (Bad Luck Protection)

Crystallized Might

Whenever you spend catalysts you gain crystallized might. Once you gain 3000 you can choose to use them to increase the skill of your choice by one level.

Note that once you reach 3000 might you will no longer accumulate more until you spend them.

To reach 3000 might, you need to spend either 3000 elemental catalysts or 7500 primal catalysts.