Hotel Transylvania 3: Monsters Overboard

You have to unlock all 4 types of Impas to solve all the puzzles and navigate through the islands to get all the treasures. Here is a list of each type of Impa and what they do:

• Vampirimpas: can lift platforms to make ramps (need 4 to make a ramp)
• Wolfimpas: can dig through sand barriers but they die in plants with smell
• Frankenimpas: can break through metal barriers, push metal shipment crates (need 3 to push a crate) and are twice as heavy as any other impa.
• Mummimpas: can create a sand bridge to cross gaps and when thrown at walls they bounce off.

Treasures are not just a collectable but also your way of upgrading your character and making the game even easier. Some examples of treasures include:

• Adding 5 more Impas to your control (15, 20, 25, 30)
• Adding damage bonuses to all Impa varieties
• Adding more time to play (Night will last up to 15 minutes)
• Adding speed to your Impas
• Adding all treasure locations on the map (during level selection screen)

As you can see these are all beneficial and worth back tracking for, if you want to upgrade yourself before moving forward in the story.

If you are still struggling to find them, then here is a video by rus199410: