You can use your own Sprites in your Animations.

First draw the Sprite Sheet and place it in the folder "Data/Textures" as a .png

Now in the Animator click 'Sprite Sheet' and select your Sprite Sheet


Click 'New Sprite'

Here you see your Sprite Sheet and can create individual Sprites



Click to select the Lower Left corner of you sprite and then the Upper Right corner.
You can drag the corners and place them exactly where you want them
On the Inspector you see the current corners indicated in pixels, you can edit them manually.
In order to make a 'Left' looking sprite you can select the Right sprite that you drew and click 'Invert Horizontal'



When you have correctly placed all corners hit Save and write the name for the Sprite, for example SpartanBodyDown

Now you can see the Sprite in the Custom Sprite List
Select a Body Part and change its sprite to the one you created.



That's it! You can now draw whatever you want in your Sprite Sheet, set the coordinates of the Sprite and use it in your Animations!

Your imagination is the limit!