Guilt Battle Arena

Although the new achievements from the title update don't specify in the achievement descriptions, they still require 3-4 players (combination of players and bots).

This achievement is quite easy. I would recommend attempting this during one of the applicable Cup challenges to save on time.

At the start of a round, you will notice two cannons, one at each end. They stop in one of three positions: Top, middle and bottom of the screen. The easiest strategy is to just stay on the ground. When a cannon is about to fire on the ground, move to the opposite side of the screen and shoot at an enemy between you and the cannon RIGHT BEFORE the cannon fires. The balls fired from the cannons can only hit one characters, so if you ensure there is someone between you can the cannon, you cannot be hit. In the event that you mess up or the other players dodge, you should still have an opportunity to jump over the lower ball (the upper one will have already passed).

If you are having issues, you can do it on versus mode to help control the number of bots and the level of difficulty. If you have a total of 3 controllers, you can boost it yourself.