Here is the full list of all 19 XNemesis SandBox achievements.
Play And Finish UnderSea Level (Works in Single Player and Two Players modes)
Play And Finish Anime Level (Works in Single Player and Two Players modes)
Play and Finish Space Level (Works in Single Player and Two Players modes)
Finish a Level Without Using Karma Effects (if Two Players mode then both shouldn't use karma effect
Kill a boss in any Level without being hit (if Two Players mode then both shouldn't be hit)
Finish Space level without getting hit at all excluding Boss (if Two Players mode then both shouldn't be hit)
Kill 2500 Enemies (Works in Single Player and Two Players modes)
Kill 5000 Enemies (Works in Single Player and Two Players modes)
Kill 10000 Enemies (Works in Single Player and Two Players modes)
In Level Designer, Tile Image(s) and paste/place at least 50 Tiles on the Map
In Level Designer, Change Health, Damage, HitEffect, HitEffect Blend Color, Awarded Score, Awarded Score Color Properties for any enemy object
In Level Designer, Draw a cutom movement path for any Enemy
In Level Designer, open Animation Helper Form for any object and play the animation (Hint: you can import template for any object)
Play and Complete a level in Two Players Mode
In Level Designer, Load Any Level and Change the Level Music from Audio, Then Publish that Level
Play and Finish Ice Cave Level (Works in Single Player and Two Players modes)
Play and Finish Desert Level (Works in Single Player and Two Players modes)
Play and Finish WarZone Level (Works in Single Player and Two Players modes)
Play and Finish Cemetery Level (Works in Single Player and Two Players modes)