There are various power-ups planned for Goomba's Quest.
Here are the one that are planned and will be added on to the new engine.
Mushroom - The common mushroom power-up that makes you turn yellow (big)
Fire Flower - A flower that can make you shoot fireballs
Ice Flower - The ice flower can allow you to shoot ice balls at enemies and freeze them
Ice Block - A new original power-up introduced in this game that allows you to shoot ice blocks and wipe out multiple enemies
Bubble - Another exclusive power-up that allows you to shoot bubbles at enemies and make them fly away
Acorn Mushroom - Like the acorn mushroom in NSMBU that makes you a flying squirrel and you can glide and do a boost with z
Carrot - Like the carrot power-up in SML
Thundershroom - Allows you to shoot a bolt at enemies and can spread to other close enemies for a chain attack (chain can combo up to 1ups)
Water Flower - Makes you shoot a water ball that splashes into a surface for a splash attack
Beet - The beet power-up from Mario forever that is found in later worlds
Star - Invincibility star