Yes, Sandslash can learn Dig at level 30 in Pokemon X and Y and level 33 in Omega Ruby and Alpha Sapphire.
Yes, Sandslash can learn Dig by leveling up to level 30. It's level 33 in Pokemon Omega Ruby and Alpha Sapphire.
No, the TM Dig is required to teach Lairon Dig. It cannot learn Dig by leveling up.
Linoone can learn Dig by using the TM Dig. It cannot learn Dig by leveling up.
Yes, it can learn Dig by teaching it with the TM Dig. It cannot learn Dig by leveling up.
Camerupt can learn Dig by using the TM Dig. It cannot learn Dig by leveling up.
Yes, Rhydon can learn Dig by using a TM. It doesn't learn Dig by leveling up.
Baltoy can only learn Dig by using the TM. It cannot learn Dig by leveling up.
Yes, Numel can learn Dig, but it can only learn Dig by using the TM and not by leveling up.
Blaziken can learn Dig, but only by using the TM and not by leveling up.
No, Probopass cannot learn Dig either by leveling up or by TM.
No, Wailmer can't learn Dig either by leveling up or by TM.
Linoone does not learn Dig by leveling up, instead it needs the TM to learn Dig.