In light of the (at time of writing) upcoming Tera Poison Greninja 7 star raids, and all the theorycrafting over what its moveset might be for how best to counter it, a thought popped into my head. It has access to Substitute, which did see competitive usage from time to time. This has me worrying about what health total the Substitute will derive its HP from.
Can Tera Raid Pokemon use Substitute? If yes, which health pool is the Substitute's health derived from, the normal form of the Pokemon or the inflated Raid health pool?
Might as well do some napkin math with Greninja, I suppose, to drive the point home. We know the 7 star raids all level 100, have perfect 31 IVs, and that when fighting them their EVs are all in Def and SpDef (they change to support the set once captured). since there is no HP boosting nature, we can just pull Greninja's lvl 100 minimum HP stat, and add the 31 from its perfect IV for a total of 285 HP. We know that Substitute costs 25% of the user's max HP, then adds 1 to the numerical value of that cost to make the Substitute's HP. And it's estimated that 7 star Tera Raids have an HP multiplier of 30x to make the Raid health bar, which in Greninja's case would be 8,550 HP.
We know from other moves like Belly Drum that the health cost to the Tera Raid Pokemon is based on the normal Pokemon, not the Raid Pokemon. So Substitute would take 25% of the ordinary Greninja's health, coming to 71 health. And here we reach the fork.
If the health of the Substitute is still based on the ordinary Pokemon, as normal, then the Substitute would have 72 health.
If the health of the Substitute is based on the Tera Raid health, it would instead be 25% of 8,550, plus 1. Which comes to 2,138 health on the Substitute, but still only costing the Raid Greninja 71 health.
Given that most of the theorycrafting of counter Pokemon is presently centered around things like Clodsire and Gastrodon negating incoming attacks, rather than actual damage dealers... I'm a little concerned for the first Raid weekend.
