The Mystery Cartoon Character Game, ongoing.

Last three clues:

4. My home base is a water planet.

5. I invented the tank my team mates and I use to transform.

6. My show is the third of three very similar 80's shows from my studio.

Well, seeing as how no one got it, here's the answer. It's Walro, from "Tiger Sharks."

1. He's the mentor of the team.

2. "Tiger Sharks" was one of four cartoons featured on Rankin-Bass's "The Comic Strip." The other three were "The Mini-Monsters," "Karate Cat," and "Street Frogs."

3. As per his name, he was able to change from man to walrus.

4. The Tiger Sharks' home base was on Planet Water-o.

5. Walro was the one who invented the Fish Tank, which he and the others use to change into fish and marine mammals.

6. "Tiger Sharks" was Rankin-Bass's third action-adventure cartoon of the mid '80's after "Thundercats" and "Silverhawks."

So I guess I'll go again. Hopefully, this one will be easier:

1. Even though I'm not human, I'm able to tell my life story.

2. My short is the longest one produced by my studio-16 minutes.

3. I played with some of the biggest names in MLB.

Last three clues. If no one gets it by tomorrow afternoon, I'll reveal the character once again, and pass the turn to whomever I choose:

4. Fittingly, my short takes place in Cooperstown, New York.

5. Like all others of my "species," I was knocked way out of the park.

6. My voice actor also wrote the script, and is an old philosopher.

I'm sure this is wrong, but the only thing I can come up with is Screwie, the talking baseball.

Not Screwie, but at least you're on the right track.

Perhaps it's Abner the Baseball?

Yes, Glowworm, it's Abner. Now to explain the clues:

1. Abner, despite being a baseball, tells his life story.

2. The short, at 16 minutes, is the longest one ever produced by Famous Studios.

3. He played with some baseball legends, most notably Mickey Mantle.

4. He's interviewed in Cooperstown, at the Baseball Hall Of Fame.

5. Self-explanatory.

6. Abner was voiced by "The Old Philosopher" Eddie Lawrence, who also wrote the cartoon's script.

So step up to the plate, and bat a thousand, Glowworm. Great job.

Thanks, just watched the short online for the first time. Pretty cute short with great voicework from Lawrence. I recalled reading something here once about a short about a baseball telling us his life story, but I just needed to put a name on him.

Well, I guess that puts me up again--but I'm not unprepared.
1. I used to be somebody's stuffed animal.
2. When she got sick, I was rescued from being burned by being brought to life.
3. However in a new twist to this familiar tale, I become a well known holiday icon.

I know this, but to avoid taking too many turns, I'll let someone else answer.

I think this is Stuffy, from the Rankin/Bass special The First Easter Rabbit.

Yes, Peter,it is Stuffy from The First Easter Rabbit.
1. Stuffy was once the stuffed rabbit of a little girl named Glinda.
2. Much like the Velveteen Rabbit, Stuffy is placed outside with a bunch of other things to be burned when Glinda gets Scarlet Fever. However, a sprite by the name of Calliope brings Stuffy to life.
3. Unlike the Velveteen Rabbit however, Stuffy's adventure has just begun as his fate is to become the first Easter bunny.

1) An impresario misunderstands my talent.

2) As I audition my golden future plays itself out before my eyes.

3) Alas, it is not to be!

It must be Willie, from "The Whale Who Wanted To Sing At The Met."

It is indeed Willie, from the short that originally formed part of the Disney compendium feature Make Mine Music.

To clarify the clues:

1) Tetti-Tatti believes that Willie must have swallowed an opera singer (or, after hearing Willie's triple range, 3 opera singers!)

2) Believing that the impresario has come to audition him, Willie sings a selection of arias, and imagines himself on the stage at the Metropolitan Opera.

3) Despite the sailors' attempts to restrain him, Tetti-Tatti finally harpoons the whale.

"Now Willie will never sing at the Met. But don't be too harsh on Tetti Tatti. He just didn't understand. You see, Willie's singing was a miracle, and people aren't used to miracles... but miracles never die. And somewhere in whatever heaven is reserved for creatures of the deep, Willie is still singing...." ​

(Still brings a lump to my throat!)

Carry on, emeraldisle!

Thanks, Pete. Now here's one I've wanted to post for quite a while:

1. You can tell just from my name that I'm a neatnik.

2. However, my buddy is a complete and total slob.

3. Ironically, my animated series premiered the same year that the show that inspired it was cancelled.

Spiffy from The Oddball Couple.

Saltybbot, you got it! Spiffy it is!

1. He's a neatnik, just like Felix Unger.

2. But Fleabag the dog is a slob like Oscar Madison.

3. "The Oddball Couple" premiered in 1975- the same year that "The Odd Couple" was cancelled. Go figure.

So you're up again, Saltyboot. Great job!

Thanks emeraldisle. I'll post one up tomorrow. Busy day today.

OK...

My series was based on a book.
I was adopted by two siblings.
Someone always makes fun of my red hair.

I have no idea. I'll leave it for someone else once again.