World 2 — (24 Stars, 6 Stamps)
Defeating Bowser in World 1 unlocks a clear pipe that brings you to World 2. There are 24 Green Stars and six Stamps in World 2.
World 2-1: Conkdor Canyon (3 Stars, 1 Stamp)
Star 1: Run to the right until you see two shifting platforms hovering over sand with a ? Block above them. Hit this block to get a Super Bell and turn into a cat. Now, climb directly up the cliff to reach a Star at the top.
Star 2: Drop back down the cliff and continue right. You'll need to pass several stretches of sand and shifting platforms until you see a Conkdor surrounded by four Brick Blocks. Stand next to the Brick Block to the top right until the Conkdor breaks it and you'll get a Star.
Stamp: Jump up the cliff next to the two rows of moving platforms and you'll find this Stamp.
Star 3: Instead of making your way down the moving platforms, head right to see a Conkdor chasing Captain Toad. Wait until the Conkdor's head is on the ground and jump on it to defeat him. Captain Toad will give you a Star for saving him.
World 2-2: Puffpod Peak (3 Stars, 1 Stamp)
You'll need to have a total of 15 Stars to break the Bowser statue and unlock this level.
Stamp: Activate the glowing pink blocks and start making your way up the course. When you see two glowing platforms against a cliff near a bunch of Galoombas, activate the further platform and then fall into the hole it creates. Now, simply activate the pink blocks and grab the Stamp.
Star 1: Keep moving further into the course and activate the various blocks to create steps back and forth up the cliff face. A Green Star is on the very left side of this cliff area. Get on the platform below it and then wall jump to reach it.
Star 2: After passing the checkpoint flag, ride the platform and enter the Warp Box. Continue to move along the course using the platforms until you can jump into the Cloud Cannon. Grab the Yellow Star in the ? Block and then jump your way across all of the cloud platforms. You'll need to grab the Green Star at the end of the course before falling back down.
Star 3: Run past the Piranha Plants and up the blocks. While on the third block, use the platform to ride to the Green Star below.
World 2-3: Shadow-Play Alley (3 Stars, 1 Stamp)
Star 1: Run right until you see the shadow of a Star on the wall. Head towards the camera and grab the Star.
Stamp: Continue right past the Piranha Plants and yellow platforms and head in the red door. Jump up to grab the Super Bellj to turn into a cat. Now, swipe at the platform below the Big Piranha Plant to destroy some Brick Blocks and make your way to the Stamp.
Star 2: Exit the red door and keep going right until you see a wall covered in pink Blurkers. Swipe at them with your cat claws and you'll find a Warp Block hiding behind them. You have 10 seconds to press the blue button and collect the Star hiding underneath the platform and behind the stairs.
Star 3: Continue moving right. When you see a red door, ignore it and go through the crack in the wall. You'll find Captain Toad shivering while looking at Bowser's reflection. Head towards the camera and defeat the wooden Koopa King. Captain Toad will reward you with a Star.
World 2-4: Really Rolling Hills (3 Stars, 1 Stamp)
Stamp: You must be playing as Mario to get this Stamp. Have Mario step on the white button with an M on it located on the small island to the right of where you come in to make the Stamp appear.
Star 1: The easiest way to get this Star is to be turned into a cat. If you aren't yet, jump on top of the three ? Blocks and jump to reveal a hidden ? Block with a Super Bell inside. Go into the clear pipe on the right. Climb up the wall and get the first Green Star.
Star 2: Enter the green pipe that's visible after reaching the checkpoint flag. Jump over the two Spiny Skipsqueaks and break through the purple blocks. Now enter the green pipe. You'll need to step on all of the tiles within the time limit to get the Star. Don't forget to jump on the cliff tiles as well.
Star 3: Immediately right of the last pipe you'll see two Spiny Skipsqueaks on a roller. Drop down into the gap just in front of them and head right to get the last Green Star.
World 2-A: Big Galoomba Blockade (1 Star)
Star 1: You'll need to defeat the three Big Galoombas to get this Star. The first hit knocks them over, so be sure to hit them again while they're upside down to get rid of them.
World 2-5: Double Cherry Pass (3 Stars, 1 Stamp)
Star 1: Grab the Double Cherry just at the front of the course. Now continue right until you see a clear pipe with wooden boxes on either side. Destroy the furthest box on the right to get a Green Star.
Star 2: Head up the clear pipe and into the green pipe. Now you'll either need to defeat or simply get past the 10 Blocksteppers in this area. There are two P Panels on the ground. You'll need to have a character standing on both buttons at the same time to release the Star. If you're playing solo, you'll need to maneuver your Double Cherry clone so that both you and your doppelganger are on a separate button.
Stamp: Go up the right clear pipe and activate the checkpoint flag. Make your way up the platforms and to the left. You'll find a group of three ? Blocks. If you're playing with a friend, one of you needs to stand on the one furthest to the left while another person hits this block from underneath. This will raise you up until you can reach the Stamp.
If you're playing solo, you'll either need to maneuver a Double Cherry Clone so that it hits you up the block or use a Super Bell to climb up the wall and grab the Green Star as a cat.
Star 3: Defeat the Hammer Bro. at the top of the block hill to make a green pipe appear. Now enter the pipe. You'll need to have four characters stand on the yellow platform on the left to get this Star. You might need the assistance of the Double Cherrys to make this possible if you're playing with less than four people.
World 2-Castle: Bowser's Bullet Bill Brigade (3 Stars, 1 Stamp, 1 Boss)
Star 1: This next area has you making your way through a procession of tanks. When you see a Cannon Block, make sure you or someone on your team jumps into it. Jump and dodge your way through the tanks until you see three Piranha plants with a Green Star in the middle. Have the cannon person or someone turned into a cat destroy them so you can grab the Star and continue on.
Star 2: You'll get to another section of tanks and you'll see a large wooden block on one of them. Destroy this to get the second Green Star.
Stamp: As you continue on, you'll see an area with a gate platform. Someone needs to quickly run over to it and jump on top to grab the Stamp.
Star 3: At the end of the course, you'll see a green pipe. Before jumping down it, use the cannon block to break the wooden panel with Bowser's face on it to get the last Green Star.
Boss fight: You'll need to knock Boom Boom down twice in order to defeat him. You can do this by jumping on him and avoiding his flailing arms, or shooting him with the cannon block. Just be careful; he turns invisible and can be hard to spot at times.
World 2-Mystery House: Mystery House Melee (5 Stars)
You'll need to run through a gambit of enemies to get all five Stars here. The easiest way to do that is to fight as a cat the whole way through.
Star 1: Defeat the two Goombas within the 10-second time limit.
Star 2: Defeat the two Koopas within 10 seconds to get this Star.
Star 3: Beat the two Cat Goombas within 10 seconds to get this Star.
Star 4: Defeat the two Conkdors within 10 seconds. This is easiest to do if you can swipe at them with cat claws.
Star 5: Beat the two Hammer Bros. within 10 seconds to get the final Green Star.
