Ok, I am now faced whether or not I should evolve Pikachu into Raichu.
The thing is... if I evolve Pikachu into Raichu, it makes Light Ball useless for battle because only Pikachu can use it, and it seems that Light Ball what I think doubles Attack and Sp. Attack. (Say it has ATK : 33 / SP.ATK : 35, with Light Ball being held, it becomes ATK : 66 / SP.ATK : 70.)
If you need to know the stats/moves...
*Stat key*
Stat : Pikachu(If holding Light Ball) - Raichu
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Lv. 29
HP : 71 - 86
ATK : 39(78) - 60
DEF : 38 - 53
SP.ATK : 40(80) - 63
SP.DEF : 40 - 64
SPEED : 69 - 75
*Moves*
Thunderbolt
Signal Beam
Surf
Volt Tackle
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What should I do... >_>
*Edit*
Well... I forgotten the Gym Leader order and went to take on the 7th Gym Leader while skipping Leaders 5 & 6. So I was kinda underleveled, but manage to pull through with 1 Pokemon that fainted, and 2 Pokemon near fainting. (Level range that I had was 26 to 30.)