Humanoid Mount?

[Stratovarius]

and there isn't a fun basis.

And fun is a VERY important point.  How many times have we heard that a caster can do something because "it's magic", but melee has to be "realistic"?

Melee does not have to be realistic. That's the whole point of the Tome of Battle. Unless someone actually thought abilities named "Girallon Windmill Flesh Rip" and "Five-Shadow Creeping Ice Enervating Strike" were realistic.

It's a game. The point is to have fun. If the rules are getting too much in the way of that, bin the rule for being stupid or rewrite it.

[Frogman55]

and there isn't a fun basis.

And fun is a VERY important point.  How many times have we heard that a caster can do something because "it's magic", but melee has to be "realistic"?

Melee does not have to be realistic. That's the whole point of the Tome of Battle. Unless someone actually thought abilities named "Girallon Windmill Flesh Rip" and "Five-Shadow Creeping Ice Enervating Strike" were realistic.

It's a game. The point is to have fun. If the rules are getting too much in the way of that, bin the rule for being stupid or rewrite it.

Isn't that Kitep's point? How many people try and ban ToB because it isn't realistic?

[7h39]

what a wonderful community! thx a lot for all the advices!

The "mount" character is an Anthropomorphic Whale (Large Size). Reading "all about Mounts" wizard article i found this

According to the Dungeon Master's Guide, a mount with an Intelligence score of 3 or higher acts like an NPC ally rather than a mount. Riding such an ally works much like riding an aggressive mount in battle (see Part Two), except that you don't have to make a Ride check to act while riding. (If your mount carries you willingly, the ride is smooth enough so your actions aren't restricted.) You also cannot make a Ride check to control the mount's actions, but you can make a Diplomacy (or possibly a Wild Empathy) check to get the mount to accept your direction. If you do, your mount acts just like a mount trained for combat riding.

Even if you cannot (or do not choose to) direct your mount's actions, you still can ride along, making your own initiative roll and possibly delaying until after your mount acts, as noted in Part Two.

then

A character could ride a mount that isn't cowardly in battle, but still isn't trained to carry a rider into combat. For example, a riding dog might be inclined to fight when danger threatens. If you're a druid or ranger, you might use your wild empathy ability (and maybe a speak with animalsspell or two) to induce some big carnivore to give you a lift. If you find yourself in a battle while still astride your mount/ally, you and your improvised mount still act on your initiative number. You must attempt a Ride check to direct the mount's actions, which is noted in the section on unruly mounts. If you fail, the mount might stick around to fight. If so, the mount moves where it will, but you still can't take any other action in the same round that you made the failed check (you spend your time just staying on).

By Str and Size of "mount" weight of the carried character is not an issue so no

I agree with the Exotic Saddle and the -5 ride malus for something that is ill-suited as a mount (Quoting Jackinthegreen)
and also with Ride modes by

You can start with the ride skill, PHB, p80

RIDE (DEX)
You can ride a mount, be it a horse, riding dog, griffon, dragon, or
some other kind of creature suited for riding. If you attempt to ride a
creature that is ill suited as a mount (such as most bipedal creatures),
you take a –5 penalty on your Ride checks.

Looking back at the Ride Skill
Guide With Knees - ignore this, as the "mount" will direct himself
Stay In Saddle - keep this and add the -5 penalty for ill-suited mount
Fight With Warhorse - ignore, as there is no need to direct your mount - both the mount and rider get their attacks
Cover - allow
Soft Fall - Allow and add the -5 penalty for ill-suited mount
Leap - Disallow.  The mount will decide when to jump and when not to
Spur Mount - Disallow.  Otherwise, people will start using this just to get more speed
Control Mount In Battle - disallow - the mount decides what she will and will not do
Fast Mount or Dismount - allow and add the -5 penalty for ill-suited mount
Special: -5 penalty for riding bareback - Allow

this is suitable for "You Break it You Buy it" forum as Total Cover Worm That Walks 2.0... throw in also Nanobots and H.I.V.E and you're golden..and disgustingly awesome.

Part 1). Get lots and lots of Fiendish Vermin, the smaller the better, especially if they have high HD.
Part 2). Because they have Intelligence, they can learn skills, likely only 1. Teach them Ride via Psychic Reformation.
Part 3). Likewise, give them Mounted Combat. Teach them Ride via Psychic Reformation.
Part 4). Use them to provide their Ride check result as your AC.

Congratulations, you have armour made of fleas.

Lolling on MasterBlaster (i didn't know it)

[Stratovarius]

Isn't that Kitep's point? How many people try and ban ToB because it isn't realistic?

Yup. We were agreeing

[RedWarlock]

Fight With Warhorse - ignore, as there is no need to direct your mount - both the mount and rider get their attacks

This one I'd disagree with, it's not about communication, it's about having the balance and control of your position and momentum to be able to make the attack and stay in your position. Thus, ride check. If you don't then you're limited to only yourself or only the mount being able to attack at one time.

[awaken_D_M_golem]

Psi has been doing this for a long time.
"Wear" your Psicrystal (as a hat) and it
rides you, and uses your ranks in Ride.

2e has a couple of giant-sized Demons
that a smarter Demon will ride (sometimes).
They're a bit of a crotchety mount though.

[kitep]

Warning:  non-serious post ahead

ok i'll say it... an Anthropomorphic Bat riding an Anthropomorphic Whale, Baleen.... 

I assume the whale still has a blowhole?  With a modified saddle, you get .......  ejector seat!
And of course, it won't be long before the ejection is aimed at the enemy, with the bat guiding the ejection with his wings like a guided missile.
And then they will decide that the bat missile will grab the whale with his bat talons and bring hiim along.  Now the enemy gets whomped by a missile and flattened by a whale!

And just wait till the bat becomes magically strong.  You'll no longer have a bat riding a whale, you'll have a bat flying around carrying a whale -- and probably dropping said whale on the enemy.

Can you imagine the bard team these two would make?  Perform(whale-song) mixed with Perform(ultrasonic shriek)

It could be quite the game

[brujon]

Kitep, i hereby gift unto you +1 for that post, for the image that was crafted into my brain was awesome indeed.

I'm not even for applying penalties now, i just want the fun.