HOW DO YOU BALANCE YOUR MONSTERS?

To clarify Craze's post, you can't do jack shit about that problem, sir.

The easiest way to speed up battles is to have less characters and enemies on the field. Slowing down the enemy in proportion to allies helps a bit too.

But the problem will never go away; it'll just be reduced.

Relyt:

don't use rm2k3 for RPGs

Somebody posted the correct algorithm somewhere around here. It involved some crazy cross multiplication. See if you can find it. It might help you speed up that all important ATB.

Determine the average damage each character will be able to do consistently (with weapons or cost-efficient powers) at the time of meeting the enemy, subtract the monster's defenses from each number, then average that to get the average damage per turn on a specific monster. Now, if you want an enemy to go down in three hits, multiply that number by three and set the monster's HP~!

I used this technique for Demon Tower, except that each "party" was each character archetype (Fighter, Tank, Healer, Mage) lumped together; Geondun was a bit more difficult, but I just used the middle damagers (Oriental and Rogue--the leather-wearing quick fighters) a players supposed average damage. I think that it works out relatively well!

MODIFY:
For Demon Tower, since I had to balance fourteen characters, I made a table (I <3 index cards) of each character's HP and DEF at every third level and then I decided on a default growth rate of enemy ATK and determined how many hits, on average, it would take each character to die.

Some characters might have gained a bit more HP during that process. =D

MODIFY 2:
You have to balance your characters before you balance your monsters. It's as simple as that. Determine what your characters can and cannot do--if nobody has a blind skill, don't through a billion brutes at them unless you know that a reliable blind-inflicting item is available. On a similar note, if the player just got a character with powerful fire skills, don't immediately have the next dungeon be a volcano.

AGI is not exactly hard to balance, just experiment a little bit and remember not to go overboard on the monster's AGI. Also, take care to give monsters SOME agi so they can actually act.

DUR HUR USE RMVX AND WORK AROUND ITS ASININE CHIPSET SYSTEM INSTEAD!

Most of the common strategies have already been explained, but I will add my two cents anyway.

1 - How do YOU keep battles interesting?

Well I like to keep things fresh. Meaning you won't see very much of the same thing on a battle to battle basis. In most rpgs, you will spend a half hour in a dungeon where you will experience monster parties like this:

Party 1:
Enemy 1 - Cave Troll A (Special Skill - Club)
Enemy 2 - Cave Troll B (Special Skill - Club)
Enemy 3 - Cave Bat (Special Skill - Drain)

Party 2:
Enemy 1 - Cave Troll A (Special Skill - Club)
Enemy 2 - Cave Troll B (Special Skill - Club)

Party 3:
Enemy 1 - Cave Bat A (Special Skill - Drain)
Enemy 2 - Cave Bat B (Special Skill - Drain)
Enemy 3 - Cave Bat C (Special Skill - Drain)

This traditional style works, but after 10-15 battles... it can get boring and you'll wind up wanting to avoid battles (unless you love to power level). Now what I do to make dungeon battles interesting without making 10 enemies per dungeon, I just change the behavior and stats of certain enemies. This way you will experience monster parties like this:

Party 1:
Enemy 1 - Cave Troll A (Special Skill - Club)
Enemy 2 - Cave Troll B (Special Skill - Quake)
Enemy 3 - Cave Bat (Special Skill - Drain)

Party 2:
Enemy 1 - Cave Troll A (Special Skill - Rock Skin) *Strong vs Arrows*
Enemy 2 - Cave Troll B (Special Skill - Quake)

Party 3:
Enemy 1 - Cave Bat A (Special Skill - Drain)
Enemy 2 - Cave Bat B (Special Skill - Ultrasound) *High Evasion*
Enemy 3 - Cave Bat C (Special Skill - Fang)

See the difference? The player won't always come across the same thing, and you're only using two different monsters (technically). You can indicate these differences in behavior and stats by changing the monster's color, or whatever else you can come up with. You can also add a twist (like absorbing enemy skills) to make this even more interesting.

2 - How do YOU balance your enemies so that it's fair, yet challenging?

This can be tricky. I think what makes battles well balanced is paying attention to what monsters you're including in the party. You can't just add three heavy hitters and call that a "challenging" battle, because you will have to constantly heal your party (and if in a dungeon, will run out of items quickly). If you want to create challenging battles, you'll have to create the core of the difficulty (lets say in this case a heavy hitter, like a dragon), and create something revolving around that difficulty (like something that will paralyze your party, or whatever else you can come up with). Lets use that enemy skill absorption idea I mentioned earlier.

Party:
Enemy 1 - Fire Dragon (Special Skill - Lava Breath--Absorb able)
Enemy 2 - Dragon Tamer (Special Skill - Lower fire resistance)
Enemy 3 - Absorption Phase (Special Skill - Disable absorption skill) *High Evasion*

This would be fitting for a boss. The Fire Dragon uses a total attack that will be even more devastating if the Dragon Tamer uses it's spell that lowers your resistance to the attack. The easy way out of this would be to absorb the Dragon's Lava Breath (disabling it's use), but the Absorption Phase prevents you from doing so until destroyed.

Try to think of your more difficult battles like solving the pieces of a puzzle. The battle is only difficult until you complete a couple of steps, then you can move in for the kill. Using methods like this will make your battles challenging, but not over the top.

3 - How do YOU go about creating monsters?

I have my methods, but I'm not going to give EVERYTHING away. =)

(The examples used above are spinoffs of some battle tactics I use in my own project. Feel free to use them if they appeal to you.)

bahleted

1) How do YOU keep battles interesting?

Making enemies in each group as distinct as possible with their own unique abilities. I've decided on giving only a few monsters the "Attack" ability while the rest do things such as status effects, draining HP and hurling magic damage at you until they explode.

2) How do YOU balance your enemies so that it's fair, yet challenging?

Besides playtesting, keeping in mind the level at which the player is supposed to be. I don't want the player to start off feeling in a pinch in every battle, so I've decided on making a difficulty gradient (emphasis on "fair" here). To begin with, every battle is winnable by simply bashing the "attack" button, but later on I plan to introduce monsters, for example with incredible ATK that rip you to shreads unless you use a certain ATK-decreasing skill.

I don't really make any calculations, so....yeah. Just lots and lots of playtesting for the most part.

3) How do YOU go about creating monsters?

As F-G said environment is key. Also I'm trying to avoid things like slimes and introducing slightly bigger monsters right off the bat. Hope it works out.