Lord of the Click II (EP)
22 Achievements
1-2h
PS4
King of duels
Play a two-player mode 10 times
72.6%
How to unlock the King of duels achievement in Lord of the Click II - Definitive Guide
Although this says 2 player mode, you do not need a second person or even controller to get these. Just select the mode and press 'A' as often as you want.
You can simply select 2 player mode and play with a single controller. Once the fight starts, spam until you have enough soldiers on the field to defeat the enemy. The faster you press, the faster your troops spawn, which will speed it up each fight.