The Good Egg Galaxy can be observed from the Terrace Dome. You need 1 star to unlock this galaxy, so it’ll be the first galaxy you unlock within the Terrace Dome. The Dino Piranha Power Star is the first star you’ll unlock in this galaxy.
Follow the Bridge
When you arrive in this galaxy, you’ll drop onto a small planet inhabited by Electrogoombas. To your right and to your left are bridges. It doesn’t matter which bridge you take as both will end up taking you to the same stoney area. When you get to the underside of the planet, you’ll want to practice collecting some star bits, every 50 star bits you collect earns you a 1-up (an extra life).
Follow another bridge upwards towards the top of the stone tower, where you’ll encounter a Luma who will transform into a Sling Star to launch you over onto another planet.
Collect the Star Chips
On this peanut-shaped planet you’ll need to collect 5 Star Chips in order to rebuild a Launch Star. Be careful though as there are lots of large boulders rolling around, and if they hit you, you’ll take some damage! Don’t forget that picking up gold coins heals you up.
Once you’ve collected all 5 Star Chips, a Launch Star will be built on the opposite side of the planet to where you started. Use this Launch Star to take you to the next planet.
Piranha Plant and Sproutle Vine
This planet is extra small and only has a singular Electrogoomba and a Piranha Plant on it. You don’t need to defeat the Electrogoomba, but you will need to spin attack or jump on the Piranha Plant to progress to the next planet. When you defeat the Piranha Plant, a Sproutle Vine will spawn. You can then climb it using Y or shaking your Joy-Con. When you reach the top of it, you’ll jump down onto a new planet.
Route A: Spiny Piranha Plant and Sproutle Vine
When you arrive on the next planet, you can either make your way towards the large, purple Spiny Piranha Plant or you can take an alternative route.
When you reach the purple Piranha Plant you won’t be able to spin attack it as it’s too large. Instead, you’ll need to use the green sprouts to attack it. Use a spin attack on a green sprout to throw it towards the Spiny Piranha Plant. When you’ve successfully hit a green sprout into the piranha plant, it will die and another Sproutle Vine will grow, taking you to the next planet.
If you are in need of a 1-up, consider taking Route B.
Route B: Flipswitch Challenge
This route involves not defeating the Spiny Piranha Plant and instead, you’ll want to find a normal Piranha Plant sitting on a warp pipe. When you defeat the Piranha Plant, you’ll be able to head down the pipe into a new area.
In this area, you’ll need to walk on all of the flipswitches to turn them yellow. You’ll need to walk upwards and sideways to make sure you get all of the flipswitches. During this area, you’ll also earn a 1-up, which is handy if you’ve been falling into blackholes.
When you’ve activated all of the flipswitches, a Launch Star will spawn and you can use it to launch yourself onto the same plant that the Sproutle Vine of Route A would have taken you to.
When you arrive on the new planet, you’ll need to make your way up a short structure covered in a few Electrogoombas. You can defeat them or move past them, but you need to make your way to the top so you can break the crystal and reveal another Launch Star. This launch star will take you to the final Boss planet where you’ll face the Dino Piranha.
When you launch yourself onto the Dino Piranha’s planet, you’ll land on his egg, cracking it in the process. The Dino Piranha will start wandering around (still with the shell on its head) but won’t attack you yet. This is a good time to collect some gold coins to heal yourself if you need to.
When you’re ready to fight the Dino Piranha, spin attack the bulb on the end of its tail. This will send it flying up and then back down onto the Dino Piranha’s head. Doing this will make the Dino Piranha very angry and he will begin to chase you. You’ll need to run around him to get to his tail so you can perform the spin attack on it again.
To defeat the Dino Piranha, you’ll need to spin attack his tail 4 times in total (including the first attack that cracked his shell). Each time you hit him he will become even angrier and even faster, making it harder to circle around him to reach his tail.
After defeating the Dino Piranha, you’ll earn your first Power Star and be transported back to the Terrace Dome.