This solely depends on your preferences. There is no one Pokemon that is much stronger than any other during the second generation. Although there is no "strongest" there certainly are Pokemon that are much stronger than others. For example, Mewtwo, Mew, Lugia, Ho-Oh, Celebi, Tyranitar, Dragonite, etc.
Ho-oh or Lugia is the strongest Pokemon in Crystal. Tyranitar would be third strongest.
Probally Mew or Mewtwo
In Pokemon Crystal, the Psychic move can be learned by certain Psychic-type Pokemon through leveling up or by using a TM29. Pokemon such as Abra, Kadabra, Alakazam, and Espeon can naturally learn Psychic as they level up. Additionally, TM29 can be obtained by defeating the Goldenrod City Gym Leader, Whitney, making it available for teaching Psychic to compatible Pokemon.
You get TM29, Psychic, from Mr. Psychic's house in Saffron City.
the strongest of its evolutions it is very strong when using psychic attacks. but he is in the top 150 strongest
'Hyper Psychic Blaster / Assault Mode' is the strongest Psychic Yu-Gi-Oh Card, ATK-wise.
Strong ground and psychic Pokemon such as Claydol, Metagross, and Tyranitar. Both ground and psychic moves are super-effective against poison. They are both multiplied by 2. A good ground type move is earthquake, but since many poison Pokemon have levitate or are flying, they can avoid this. It depends on dual types, abilities, available moves, etc., of both Pokemon, but the strongest Pokemon against poison Pokemon generally would be the strongest psychic and ground Pokemon. Some excellent psychic and ground Pokemon (strongest is quite subjective, so there's no definite answer) are Metagross and Tyranitar, respectively. Claydol is a strong Psychic and Ground dual-type Pokemon.
Gothita is a Psychic type pokemon.
The strongest Wobbuffet you can find in crystal version are in Cerulean Cave, they might be a little hard to find though
Dark Pokemon are Psychic Pokemon's weakness.
psychic type pokemon are weak against psychic steel and dark
psychic psychic