Marill has better base stats then Lotad though Lotad is an Duel Water/Grass. On paper Marill is superior however it is more of a personal play style choice.
You can obtain a Lotad in the Safari Zone.
Marill evolves to Azumarill and its preevolution is Azurill.
Lotad cannot naturally learn it but it can be taught Thief with a Thief TM. Lotad's evolved form Lombre learns Thief at Lv. 37.
Marill evolves into Azumarill at level 18.
Marill doesn't learn surf naturally; must use hm
Lotad turns into a Lombre which is pretty much a water Pokemon and being very good. Another is Marill and Corphish. (There's also of course Kyogre, but he's a bit harder to find and catch)
lotad evolves into lombre at lvl 14
in the great marsh but its weak better catch a buizel
Lotad can appear around the early routes.
Lotad's final form is Ludicolo.
Marill is the evolved form of Azurill. Marill can evolve into azumarill. HOW TO EVOLVE MARILLUTIONS: make azurill happy, MARILL! Lv. 28 (i think)marill.. AZUMARILL!! ^^^^^^^^^^ made that up!
Lotad evolves into Lombre at Level 14.
You can obtain a Lotad in the Safari Zone.
Yes, Marill can evolve into azumarill.
Marill evolves to Azumarill and its preevolution is Azurill.
Nobody knows how to get a marill in the world so bye bye
Marill evolves at level 18