Cranky Ducklings are a variant of Mystery Duck which appear in Mystery Duck Challenges.
- Cranky Ducklings are found in some Mystery Duck challenges. A new Mystery Duck challenge appears every 24 hours, but a different type of Mystery Duck will likely feature.
- When a player collects ten Cranky Ducklings and completes the challenge, it is added to the Mystery Duck counter (Ten Cranky Ducklings counts as one Mystery Duck). For every three Mystery Ducks collected, a new Duckie costume is unlocked.
- Cranky Ducklings require one drop of Purple Water each to collect and fill (ten total). All other Steam, except Steam will kill Cranky Ducklings. If one of the ten Cranky Ducklings is killed or if the level is completed without them all being collected, the level fails.
- Once all Duckies that are unlocked with the Mystery Duck are unlocked, Mystery Duck challenges will no longer appear, thus, neither will the Cranky Duckling.
- While Full, Cranky Ducklings take on the appearance of a full Cranky Duck albeit much smaller, though with larger eyes compared to its body.
- While Empty, Cranky Ducklings have the shape and features as his full version, though in shades of green.