You can get up to, like, 23 of these, but I've never gotten them all in one game. You'll see why in a minute.

In Home World's Arni, enter the cafe and talk to the girl swaying in front of the counter. You don't have to really pay attention to what she's saying, just do it. Talk to the same girl in Another World, then go back and talk to the original girl. She'll give you the Book of Poems (pictured at right). Show this book to the girl in Another World, and she'll give you a rainbow shell.

When you first enter Another World's Arni and check the elements lady's cart, you'll find a Rainbow Shell, but the mean lady won't give it to you. hrmph. Fine. Well, after you get stuck in Home World for an eternity, but then are finally able to get back to Another World, the citizens of Arni have secuestered themselves in the courtyard, including the elements lady. But she left the Rainbow Shell behind cause she's a moron, so go pick it up now.

Put Skelly back together, then talk to the guy on Another World's Water Dragon Isle (the same guy who gave you Skelly's Sturdy Ribs). He'll now give you a Rainbow Shell.

When on the Isle of the Damned in Home World and yer tryin to get the Einlanzer, you fight the Wight Knight if you woke him up with a WillO'Wisp. His rare (and I mean RARE) drop (as in, yer spoils) is a Rainbow Shell. RARE drop. So don't kill me if you don't get one from him. I usually just get Iron, and I've played this game somewhere bordering on twenty times... ^-__-^;;

This one's pretty much like the Wight Knight... When in Fort Dragonia and trying to get Serge his real body back, you fight Dark Serge in the White Crystal area. A very rare steal (again, RARE, like a pink-spotted leopard) is a Rainbow Shell. More than likely you'll just get a Trashy Tiara (... why did Dark Serge have a tiara? Does he put it on sometimes and tell himself how pretty he looks? ^O__o^;; ).

On your first visit to Termina, talk to the Churros guy and tell him to lower his prices to 70g. Leave the area. Now, anytime afterwards, he'll give you free churros that'll refill your HP and remove status effects. After becoming Serge again, go back and talk to this guy, and he'll be closing up shop. He'll give you the leftovers, and when you bite into it... *crack* OW! Hello, you just chipped a tooth on a Rainbow Shell.

After the invasion of Another World's El Nido by the Porre military, enter Viper Manor (you must have Norris in your party, or else they won't letCHA in), go into the trap room (the one between Luccia's lab and the stairs), take the Decor Shield (pictured at right) off the wall, put it on the statue missing a shield (back wall), fight off the Man-O-Wars, open the panel in the pillar in the back left-hand corner of the room, flick the switch, then move the viper statues into their niches. Go through the secret entrance you just opened and one of the chests back there contains a Rainbow Shell (the other one has General Viper's Viper Venom weapon).

Onboard the S.S. Zelbess, play the game in the casino and win a rank 1 prize. The first time, it'll be a Rainbow Shell (after that, they'll just give you Denadorite). To win, keep pressing Start after the wheel has started moving, and when you see the red tip of the spinner thingy on S(outh), or between south and southwest (southwest is halfway between S and W), quickly press Start and X. Ifyer reflexes are fast enough, the red tip will land on N, and you double yer points (if it lands on S or you end up with 0 points, you'll have to start over again).

During the whole Earth Dragon thing, talk to the captain to find out that they can't find the entrance. Jump into the quicksand to enter the underground cavern, jump into the sand boil to get back topside, then talk to the captain twice. He'll give you a Rainbow Shell for helping them out with their expedition.

In the Sea of Eden (not the Dead Sea, mind you), upon entering Chronopolis, you have to fight a boss (PolisPolice, pictured at right). Sometimes when stealing from him you'll get a Rainbow Shell.

In Chronopolis, go to the third floor. Enter the room to the left of the elevator, then enter the room in the back. Open the chest to receive a Rainbow Shell.

During the Burning Orphanage sidequest, defeat the LavaBoy in the first room, then check the clock for a kid to jump out. Talk to him to get a Rainbow Shell.

In the same Burning Orphanage sidequest, defeat the LavaBoy in Granny Lara's old bedroom, then inspect the bed for a girl to run out. Talk to her to get another Rainbow Shell.

This one can only be done if you did the Burning Orphanage sidequest: Take Kid to see Luccia in her lab in Viper Manor. Luccia gives Kid a letter from Lucca, inside of which is a Rainbow Shell.

Go down into the El Nido Archipielago in Another World. On the first level is a Rainbow Shell in a chest.

In the same area, go down into the depths, and there's another Rainbow Shell in the chest on the far right-hand side of the area.

There's one in Terra Tower, in the area after all of the climbing branches. ... yeah, I know, real descriptive, huh... ^>__>^;; It's Terra Tower, fer cripes' sake! Sheesh.

Also in Terra Tower, in the area with all the ladders, is another Rainbow Shell.

Again, Terra Tower, but this time in the area with all the freaking staircases.

If you steal from the Criosphinx, you might get a Rainbow Shell.