At level 45.
You can't catch Metang in emerald. You can only get Beldum, and then you can evolve it into Metang.
at lv 45
It evolves at lvl 45.
Beldum evolve into Metang at lv20 and Metang evolve into Metgross at lv45
metagross
Did you mean Metang? Because if that's the Pokemon your talking about it evoles level 45 into a Metagross.
Metang evolves FROM Beldum at Level 25 Metang evolves INTO Metagross at Level 45
You cannot catch a Metang in Pokemon Diamond. To get one, you can evolve a Beldum.
65
Evolve Beldum.
Metang evolves into a Metagross at level 45.
In Pokemon HeartGold, Metang evolves into Metagross at Lv. 45 .