Can The Ability Electric Surge AND Choice Specs Be Stacked For Extra Damage?

Question

Okay So We Know Tapu Koko's 2 Highest Stats Are Its Attack & Its Speed & Has a Ability Called Electric Surge (Gives 50% More Power To Electric Type Attacks) Also Choice Band Gives 50% More Attack SO With That In-Mind: I Wanna Know If The 50% From The Electric Surge Ability & The 50% From The Choice Band Item Can Stack Up To Make 100%?

Comments

Yes, they would stack, but I don't think they stack in that manner.  The damage calculation formula is more complex than that, and modifiers are placed in different parts of the formula.  I'm not familiar enough with the formula to know where those modifiers are placed to give you a clearer answer.

Answer 1

This involves a bit of math, but it shouldn't be too hard to understand. Damage modification can be written in function notation. In your example, choice bands and electric terrain both boost damage by 50%, which would be f(d)=d+50%d. If both choice band and electric terrain are effective, the function would be applied twice to the damage.
f(f(d))
f(d+50%d)
f(d(1+50%))
f(d3/2)
d3/2+50%d3/2
d3/2+d3/4
d(3/2+3/4)
d(6/4+3/4)
d9/4
The damage would be multiplied by 9/4, or 2 and a quarter. It's supported by this calculator.

252+ Atk Choice Band Tapu Koko Wild Charge vs. 4 HP / 252+ Def Eviolite Chansey in Electric Terrain: 441-519 (68.6 - 80.8%) -- guaranteed 2HKO
252+ Atk Tapu Koko Wild Charge vs. 4 HP / 252+ Def Eviolite Chansey: 196-232 (30.5 - 36.1%) -- 50.8% chance to 3HKO

As you can see, 441 is about 196*9/4 and 519 is about 232*9/4.
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