You'll create a chain of words, given the first and last words of the chain. Fill in the middle words with valid transformations between them.
Valid transformations:
Insert a letter: CAT → CART
Remove a letter: CART → ART
Swap a letter: ART → ARE
Rearrange letters: ARE → EAR
Circles next to a word indicate if it is a valid word, and between words indicate if the transformation is valid. Green means valid, and red means invalid.