How can I teach my Pokemon dig?

Question

I earlier had TM 28 (dig) in Pokemon emerald which I used on my Swampert. Later I made him learn earthquake instead. Now I want dig for the Regis. But I cannot find an easy way. Please help.

Answer 1

Nincada learns Dig naturally at level 37, and Trapinch learns it at level 41.

Answer 2

Besides TM 28 Dig that you get from the Pokemaniac in Falabar Town, there is no other way to receive another TM Dig without the use of some cheating system/program.

That being said, you stated that you want Dig for the Regis, but only Regirock out of the three can learn it at all - and unfortunately that's via TM Dig as well.

However, if you really want Dig, you can indeed catch a Nincada or Trapinch who learn Dig at level 45 and 41 respectively. Or, if you don't want to catch one and instead have other previous generation games, you can catch a Diglett from Diglett's Cave, migrate it to Pokemon Emerald, in which Diglett/Dugtrio can learn it at level 17.

Hope I helped! :)