So if I take my Eeveelution that is level 17 to the move deleter and make it forget all its moves but Last Resort, will it be usable in battle without using other moves first?
Last Resort will fail if it is the only move in your set, you must use all other moves in the set first, and it will fail of it is the only one. However, if you only have 2 moves you can easily use the first move then spam last resort to your hearts content.
Sources: Personal Experience
How to change your username
How to add a user avatar
Why was my post hidden?
The points system
Flags vs Downvotes
Type a Pokemon name, type, move or ability to see instant results.