Gengar help
Which Gengar should I power up?
a) 1698 CP 91.1 (131315) SC SB
b) 1679 CP 82.2 (15814) SC SB
So both are the same level, obviously one has max attack stat while the other is 13. I'm not too sure which one to power up.
Answers
I don't know which order you posted your stats
Att / Def / Sta
or Sta / Att / Def
here is a great google table to compute the relevant breakpoints:
https://goo.gl/mhYfmz
I guess you want Gengar to attack Mewtwo so assuming you list stats Att/Def/Sta:
On offense, 13 attack IV SC gengar reaches the last breakpoint at level 33.5 while with 15 attack you require level 32.5
In order to survive 3 confusions and make Gengar viable against confusion Mewtwo:
13 def / 15 stamina -> level 33
8 def / 14 stamina -> 36.5
So I would power up the first one to level 33 (if its stats are ordered (att / def / sta)
To add on to this, if you don't plan on maxing the Gengars, then power up the one with 13/13/15 to 33.5.
You'll hit 2 breakpoints, surviving 3 Confusions vs Mewtwo (so that you can use Shadow Ball) and a Shadow Claw damage breakpoint which is useful against Psycho Cut movesets.
The Gengar wth 15 attack reaches a Shadow Claw damage breakpoint sooner at level 32.5 but you don't want to leave it at that level because then it is useless vs Confusion.
The one with 13/13/15 requires less dust and candies to make it stronger against all of Mewtwo's movesets. Both are level 23, taking it to 33.5 costs 90 candies and 99k dust, level 36.5 costs 144 candies and 144k dust, and they're going to perform about the same.
Attack is not always weighted higher. The effect of IVs in increasing CP depends on the relative increase that IVs have on the base stat. It's not simply "attack is better for CP".
Attack IV usually has more weight because it is not square rooted in the CP formula.
e.g. if a Pokemon has 100 in all stats, 15 attack IV is a 15% increase in it's base attack and therefore a 15% increase in it's CP. (115 / 100 = 1.15)
15 defence or stamina IV is a 15% increase to that stat but the CP formula square roots said increase resulting only in a ~7.2% increase in CP. (1.15^0.5 = ~1.0724)
In the case of Gengar (and Alakazam) who have extremely high attack and also low stamina, points in stamina IV have a large enough relative increase that the resulting increase to CP is still higher than the effects of attack IV even after being square rooted.
Gengar's base attack is 261, so 15 attack IV increases it to 276, a ~5.7% relative increase (276 / 261 = ~1.0575), and therefore a 5.7% increase in CP.
Gengar's base stamina is 120, 15 stamina IV increases it to 135, a 12.5% relative increase (135 / 120 = 1.125), which results in a ~6.1% increase in CP. (1.125^0.5 = ~1.0607
