This is an easy achievement but it will require you to be strong enough to clear the item world
- Masked Hero using the Nether Express and as much movement boosting items as possible ex Winged Boots, Accelerators or higher. If you have 20+ movement you will be able to clear most stages in one move if no gatekeeper is protecting the gate. The Masked Hero is a "Flying" type so he can walk right by enemies that are blocking a path.
- A Medic. The medic class contains an ability that allows a character to move\attack again as well as strong healing spells. Very useful for maps you cant reach the gatekeeper or gate on one move. Medic Class is part of the DLC
- 1-2 High damage dealers. Stella and Tyrant Valvatorez are ideal for this given the Area of Attack of their Final tier unique skill. This makes it easy to clear any areas blocking your way to a gate keeper or kill an Item General\King\God
Now there are 2 ways to get this.
1) There is a mystery room that contains Axel and Pink with a bunch of statues in the back. This room is extremely rare and I have only seen it once. Speak to Axel until he picks a fight with you then just destroy the statue before killing both Axel and Pink
2) These statues do appear in the item world. This is how I unlocked this achievement. When traversing the item world, keep an eye out for Axel Statues. There are only 3 types of statues, Hugo, Valzy and Axel. I cant confirm this but I didnt bump into one until near the top floor of a legendary item. I dont know if its 100% random or if it more likely appears on tougher stages. Simply just destroy the statue on the map and the achievement will unlock. Axel statues should be the ones with their pointing upwards. If you are unsure, if you hover over it, it will say who's statue it is.