You can't catch Metang in emerald. You can only get Beldum, and then you can evolve it into Metang.
At level 45.
at lv 45
It evolves at lvl 45.
you can't find metang in Pokemon diamond you have to get beldum in swarm when you get the national pokedex and then evolve it
After defeating the Elite 4, go back to Mosedeep City and go into Steven's house. There will be a Pokeball on his table containing the Pokemon Beldum. Beldum evolves into a Metang at level 20.
You will have to evolve a metang.
Did you mean Metang? Because if that's the Pokemon your talking about it evoles level 45 into a Metagross.
metagross
Metang is a Steel and Psychic type pokemon.
Metang evolves FROM Beldum at Level 25 Metang evolves INTO Metagross at Level 45
Beldum evolves at Level 20 into Metang. Metang evolves at Level 45 into Metagross. Also, if you have other questions about Pokemon, go to this website attached: http://www.serebii.net/index2.shtml This is the best website about Pokemon! I hope I helped!