How do you all choose which units to be the enemies in an RPG?

Usually I'm pretty good at grading the difficulty. After playing StarCraft for years, I know each unit's strengths and weaknesses.

For example, if it's a steep difficulty grade at the beginning, sometimes I like to start out with melee enemies, then introduce one rogue ranged unit to catch the player off guard. I also take advantage of multiple enemy players and give them different upgrades so I can reuse the same unit type at different points in the game.

This is usually easy for most RPGs where the player only has one unit, or maybe a few like in Elements. But what would you do on a map where the Player commands MANY units throughout the game? Many as in more than 20?

This becomes incredibly complex, trying to balance out unit types and strengths. I'm beginning to think I should just forget trying to match types and just go for looks and style -- make the cooler units stronger.

How do you choose enemy units in any RPG? In many RPGs it's because of what they resemble, of course (e.g., usually you wouldn't call a zerg unit a "human"). How else? Do you ever just choose randomly?

Some of time hard for people to balance it out when comes to melee vs range units.

I mainly balance it out depending on how how many players I add for a game, but most of time I make 1 - 2 player maps.

So If I was to make it a 1 player map and hero was a melee class I'll try balance it out giving hero maybe a rush ability to push him in next to range target or speed or even enough hitpoints to take the damage without being killed before he reaches target.

I like to mix up enemy parties with range n melee depending where you're at during progress of the map. But it can be hard to balance it out at times not making it extremely hard or too soft core for players but in middle some of time.

I never randomly select a enemy, I mainly work out things like what era is it, what type of monters would you be vsing, how will I balance it out so that not too hard start off with and gets harder as you go, will I need that unit near the end or middle, will I reuse that unit with upgrades.

Some of odd things I think about..

A lot of times you can go for looks. Most of the time you can just balance the units hp/armor/attack to the approximate difficulty of what you think it should be. The only time you really can't is when you're using air units vs melee units, for the obvious reason. There are a few other situations I'm sure, but it's really the hp/armor/attack that matters most, unless there are specific skills like cloak, storm, or ensnare involved.

Size can be a factor, along with RoF, but yeah. The only major things are whether they can hit eachother.

I think it really depends on your story and also the looks of the unit. Or for whatever reason, if RPG, a zergling may be described as "human" maybe because he was previously a human and changed somehow (magic?) or maybe even that they wear costumes of what they see themselves as.

As for strengths and weakness of each unit and balancing, I'm also having trouble with that. I am looking at fire rate, range, type of damage, and special abilities.

I find a lot of maps either screw up by overpowering one unit over another, especially the marine, or realizing the marine could be too powerful, so they make it very weak... Also the combination of the team(s) that may be involved in a battle at the same time. I also included Roles, as in is the unit a meatshield, or does it mainly do damage with low defense? Or maybe it's a balanced unit that's decent with both but does not excel in anything in particular?

So I have a bunch of variables which I then wipped up a formula (of which isn't really working, but the variables still exist)

Range - The unit with the shorter range is likely to be attacked more

Damage Type - There are different kinds of damage, Concussive and Explosive, for example
I don't mind a unit having Explosive Attack, so I don't add or negate a units damage based on that, but for Concussive damage I do add more damage as it basically sucks because it goes all the way down to 25% on large units. There is also NORMAL DAMAGE, where the size and type of armor the unit has is exempt, meaning if the normal damaging unit is to hit 50, it will hit 50 regardless of unit type. The marine is, for example, a normal damage unit. And because of normal damage, I might add a little to Explosive attack, and a bit more to Concussive.

Splash - I generally cut down a units damage for RPGs due to their ability to splash...

Ground-only: Some units that are ground only deserve a little bit more damage in RPGs, IMO.

Special Abilities: Special abilities like stim makes the marine and firebat fire almost if not twice as fast, so I do a major cut in their damage.

Fire rate: The fire rate of a unit is a major factor... I personally have to be careful with this one, because while the Marine (15 cooldown) technically fires twice as fast as the Dragoon (30 cooldown) should not mean the dragoon should do twice as much damage as the marine. Why? Because while the marine is hitting a unit twice as fast, the armor is also calculated twice.

So we have 3 units:
Marine, Dragoon, and Zergling.

Marine does 30 NORMAL damage
Dragoon does 60 EXPLOSIVE damage.
The Zergling has 20 armor and 200 HP.

One shot from the Dragoon would cause the zergling to lose 40 hp.
Since the Marine shoots twice as fast as Dragoons, in the goon's 1 shot, the marine would have attacked twice, but the damage would only be 20. The first hit would be 30-20 = 10, the second the same, therefore 20. But also the Dragoon actually only cause 50% damage to small units due to its explosive attack, so the 60 is reduced to 30, which means they actually do the same amount of damage at the same rate...

The marine then still has the potential to stim, but even attacking faster with stim, one still has to keep in mind that whatever damage he is doing is still negated from the armor each time.

Then there are personal ideas, such as Roles.

If a unit in a group is meant to be a meatshield, maybe he'd get a bonus in armor, but a penalty in damage. If the unit is suppose to be a damage dealer (DD), then maybe it'll get a bonus in attack but penalty in damage (perhaps best with ranged units). Then also if you want some units that are balanced in both, but does not excel in either. Anyway, personal preference and creativity could also bring extra twists to the balancing system. Even the frequency of battle and the amount of teamwork you'd like in the RPG would determine how you would want it to go...

Once you've created a formula with all these (and more), apply to all units, and give an edge to heroes perhaps by giving them more hp over the monsters or simply allowing them to upgrade. To prevent the bad guys being as strong as the heroes at the beginning, maybe you could modify hp percentage and start them out at different levels up upgrades.

Anyway, these are just what I'm considering to balance my map and I myself have not found a fitting formula that will work with the amount of fighting frequency and to maintain balanced as the heroes get upgrades and gain HP by leveling up.

So here are what I observe, let me know yours so I can take it into consideration on my own map.

Thanks

You're theories are sound. But your facts aren't.
Correct.
Wrong. 75% to medium. 50% to large.
Not enough info.
Splash does less damage the further the "splashed" units are from ground zero. Each pixel takes off [something along the lines of] 5%.
Under no circumstances will a unit do less than 50% damage before armor calc.

There is a reason there are very few medium units [especially units which look like medium, but are in fact large.
It is because they take reduced damage from a LOT of units.

Woops, sorry bout that, I didnt read the whole thing thoroughly. You DID calculate dragoons damage beign halved, but you didn't take into account armor.

Keep in mind also, that there are more explosive guns than concussive. So a small unit will [GENERALLY] fare better than a large one.
Also, large units get walled in easier, not to mention the HORRORs of dealing with DAs as a unit. DAs are the fattest of the fat, they get stuck on OPEN GROUND. Small units are also usually the faster ones. [Stim, zealot and ling upgrades etc.]

You also have to take into account how many units can hit it.
In melee, you can get about 4 units to surround a marine/zealot/zergling.
Whereas a dark archon can get up to 20 zerglings.
It's also a lot easier to stop a large units escape. A large unit only takes 4 units to halt, whereas a small unit can often slip out.

Take into account what they do in ORPGs. If you are having 20+ units, you may want to just make it an ORPG.

what's an ORPG?

if you mean an online role playing game, then what does that look like in Starcraft?

I believe it's an Open RPG, like one where there is really no ending, and no true storyline that continues throughout the map.

Okay here is what I like to do....but I will explain it.

For example if you are using Ling for enemy, and you want to use it later on in the map...then I give the Ling like example 800 health. And I set their hp % to the required amount depending on the stage in the rpg. So for the beggining it could be at 25% and as they progress through the game setting it higher and higher until it gets to the point where they can be at 100%. That way for me at least, I can use the enemy unit throughout the whole map and have the same difficulty of killing it. I either do this via Location Areas and Triggers, or manually placing the units and setting their HP %.

Edit:

I balance the units out based on attack speed and range. Like for example in a normal melee game with standard settings, it takes 2 marines to kill 1 ling...so I use that type of theory myself as well. Basically if you have a good storyline and you follow through with it, then it should turn out good.

You have to take into account the zerg regeneration too.

A 5hp 50 armor zealot is a helluvalot easy to kill than a zergling with the same stats.
Example:
You have a unit that does 20 damage, so against both, it'll do 1 damage per shot.

First shot:
Zealot - 4hp
Zergling - 4hp

Second shot:
Zealot - 3hp
Zergling - 3hp, regens 1 = 4hp

3rd
Zealot - 2hp
Ling - 3hp

4th
Zlot - 1hp
Ling - 2hp + 1 regen = 3hp

5th
Zlot - Fallen
Ling - Still going strong at 2hp, regen coming too.

While it means a LOT less for high HP units, when working with low-hp, it gets tricky!