Banjo-Kazooie

After you save your sister, go back to the quiz area.

Walk through the quiz board freely, then take a right up to the lair of Gruntilda.

Make your way to her cauldron so he can blast you up to the roof where you will fight here.

There are 5 patterns of attack you must do against Gruntilda to win.

1. Dodge her flying broom attacks and peck her on the back.
2. Dodge her fireballs, climb on the edge of the roof and spit some eggs at her.
3. Take to the air via the flight pad and dive bomb her midair while dodging her fireballs.
4. Shoot eggs into the jinjo statues (4 of them) to activate jinjo attacks on Gruntilda.
5. Shoot eggs into all 4 sides of the big Jinjonator statue to activate the Jinjonator against Gruntilda.

Note: make sure you use your gold feather invulnerability against that homing white fireball or you will get hit by it. Also, make sure you upgrade your health to double health and stock up on the BIG feathers and eggs before the fight using those extra music doors around the cauldron.

After completing Grunty's quiz game, Banjo will save Tootie at last. The credits will roll, and then you'll find yourself at the start of Gruntilda's lair. Make your way back to where the quiz game took place, and this time after reaching the end, go right and up the path. This will lead you to a new character named Dingpot. Dingpot has the ability to send you up to the boss battle that you need to beat in order to earn the achievement.

Preparation:
Grunty's boss battle is an absolute pain if you're not too familiar with platformers. First things first, make sure you've found a majority of the honeycombs in the game, you want your health to be upgraded to 8HP, which is the max. I completed the boss battle with one hit point left, so I guarantee you that having all eight is worth it. You don't need to worry about scrambling around for resources, however you should have almost all music notes collected. You will basically want to have earned the Music Maestro by now. Having all 900 notes will unlock three doors surrounding Dingpot. These doors open up to reveal different items that instantly take a specific resource to the maximum amount you can carry. There's one for eggs, another for red feathers (flight) and another for golden feathers (invulnerability). Restock with these before entering Dingpot. As a side note, Cheato's cheats can double your inventory amount for each of these items. I completed the boss battle without Cheato's cheats, but if you're having trouble you can go and activate them at the Treasure Trove Cove castle room floor. Keep in mind that Cheato's codes will not work unless you have actually found him, and he's given the code to you.

In Case of Failure:
Take a breather. This fight was very frustrating when I tried it. If you're having problems and you can't concentrate, take a break, go outside, do something else. Come back the next day. If Grunty beats you during the boss battle, you will respawn outside Dingpot. Instead of jumping back in right away, go back the way you came and in the same room as a cauldron, you can find an extra life sitting in the window sill. Jump up and take this. It will respawn if you die, which means you can have as many attempts at fighting Grunty as you'd like. Just remember to grab it before you jump back in.

First Stage:
Grunty will zoom by you, trying to run you over with her broom. Just keep walking back and forth, and if you feel like you're cutting it too close, use Kazooie to run. After a series of swipes, Grunty's broom will break. Instead of pecking, shoot her with eggs. This prevents you from getting too close and accidentally taking damage. This is a fairly easy stage in the boss fight, so do your best to avoid getting hit. Don't give up if you do, but again, just play it safe. After you've hit her a few times, she will throw a green, homing fireball at you. The only way to avoid taking damage is to use a golden feather or two. She will then drop a health point, which you should avoid taking if you're still at full health. Don't worry, it won't despawn.

Second Stage:
Grunty will then shoot fireballs from the edge of the map. Take cover by hiding behind the walls that are right in front of her. Either misdirect her fireballs by juking back and forth, or wait for her to stop so you can get an opening. Shoot three eggs and then take cover again. She'll go to four different spots around the tower before throwing another green fireball at you. As before, use your golden feather(s) to avoid taking damage. If you took a hit, grab the health point she dropped before. She'll drop another, but try to save it for after the third stage if you can afford it.

Third Stage:
In my opinion the most difficult stage because of how hard it is for me to aim while flying with inverted controls. A flight pad will appear and you'll have to use it to continue. Attack Grunty with an aerial attack and she'll shoot fireballs at you. To me, it wasn't so much about waiting for her to stop attacking so much as it was me waiting for her to stop moving. You don't want to miss her, as hitting the ground causes you to take damage, and if you're aiming down and you fly past her and the tower, you could fly right off the map and get an immediate game over. Once she makes a comment about needing a shield, fly back down to the tower and wait for the fourth stage. If you need any more HP and you still have some lying around, this is the time to pick it up.

Fourth Stage:
Grunty will begin to fire off fireball erratically. Use Kazooie to sprint around until the Jinjo's show up. Now fire four eggs into each Jinjo statue to activate it. The sooner you can get this stage over with the better. I couldn't discern any type of attack pattern from Grunty, so just move fast. Once all four Jinjo's have been activated, a fifth, giant Jinjo statue will appear and the final stage will begin.

Fifth Stage:
Grunty will fire a series of fireballs at you. Strafe back and forth (serpentine) to avoid these. To finalize her pattern, she'll fire a green homing fireball (listen for her charging sound, which you should know by now). Use a golden feather to avoid taking damage, and now use this opening to fire four eggs into one side of the Jinjo. Do this another three times until you've filled up the Jinjo and it's unleashes it's fury on Gruntilda. As the cutscene plays, the achievement should pop.

Additional Hints:
There are eggs, red feathers, and golden feathers all around the edge of the tower. These will respawn after a short time, so you will technically have unlimited ammo. Just be cautious if you have to pick it up, as Grunty can knock you off the tower and kill you instantly.

Good luck!

DISCLAIMER: This will not be saved towards your progress, I merely used it as a stepping stone to getting the achievement. 😂

1: go to treasure cove and find the place where you enter cheat codes area.
2: enter CHEAT into the sandcastle floor and follow it up with AGOLDENGLOWTOPROTECTBANJO; this will allow to be invincible the whole entire time while having your ability up.
3: head up to fight the last battle
4: where this code really comes into play is being able to see what the timing is where you have an opening to throw eggs into the whole of the different types of statues of the mini Jinjonators. This includes the last fight where you have to hit all four sides of the big Jinjonator.
5:Wait until the witch throws the white/bluish ball at you, then you may have 1-2 to throw as many eggs into one side of the mega Jinjonator. Once that side is complete, rinse and repeat.