Just a bit more info for other members and a comparison between the both, followed by own opinion.
Mewtwo;150;:
HP: 50
Att/Def: 25/ 15
SpA/SpD: 25/ 15
Base EXP Value: 250
Level Up Moves
L 1 Disable
L 1 Confusion
L 11 Barrier
L 22 Mist
L 33 Swift
L 44 Recover
L 55 Safeguard
L 66 Psychic
L 77 Psych Up
L 88 Future Sight
L 99 Amnesia
Mew;151;:
HP: 35
Att/Def: 20/ 15
SpA/SpD: 20/ 15
Base EXP Value: 250
Level Up Moves:
L 1 Pound
L 10 Transform
L 20 Mega Punch
L 30 Metronome
L 40 Psychic
L 50 Ancientpower
Consider which levels faster
As you can see, both Mewtwo and Mew level up at the EXACT same speed.
which has better level up moves
I think Mewtwo has better in level up moves. Attacks like disable are useful to temporarily paralyse strong opponents, while confusion can sometimes confuse the foe. Mew's only attack will be pound in the early floors(transform is useless).
which has better base stats
Mewtwo and Mew have same defences, but Mewtwo has more HP and more offensive power than Mew. So, Mewtwo is better in stats.
So far, Mewtwo is better than Mew in everything.
remember mew can learn any tm you bring in
This is the only thing that makes Mew sometimes better. Frustration (OHKO in early floors), thunderbolt (monster houses) & bullet seed (powerful move) are some the best moves for Wish Cave but Bullet Seed can only be learnt by Mew. Also, just for those who are curious, Mew can travel over water (thus escape from foes) while Mewtwo can't.
I used Mewtwo and I was successful. Disbale Jirachi, then unleash strongest moves. Mew can use bullet seed, and maybe paralyse using thunderbolt, but still Jirachi can attack and kill you. So if one dies in a boss battle, you can't send SOS mail, hence you have to go through the whole dungeon again
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