one more thing to think of when coming up with skills, try and make them independent of each other, i am not making characters with set skills...this game consists of creating your own custom heroes. so i can use skills that are dependent on other skills and this will require people to pick multiple skills to make one skill worth while getting

Name - Charge
Effect - The hero will run in a direction until it meets an obstacle like a wall. The first enemy unit (preferrably a hero) will be pushed with the hero until the hero rams the enemy into a wall or tree or other stationary object. All other enemy units will be pushed aside and dealt damage. The longer the hero goes, the faster he goes, and the more damage he does, but the more tired he gets. The hero will be stunned upon impact depending on how fast he was going. It also takes a little bit of time to slow down.
Type - Physical
Changes Per Level - Damage done, and possible the speed. The cost would probably go up.
Other - May need tweaking.

Name - Shock Beam
Effect - The hero will unleash a beam that goes in a straight direction for a certain m. Enemy who have been hit by it has a 50% chance of getting stun.
Type - Magic
Changes Per Level - Damage done, the chance of stunning and the mana cost.
Other - The main focus on this spell should be on the ability to stun the opponent where the hero and allies can support the attack.


Name - Agitated
Effect - It will cause the hero to become enraged. Damage will increase(Maybe 20-30%) for a short period of time. However, the defense ability will be comprimised. The defense will decrease as a result.
Type - Active Support
Changes Per Level - The mana required, damage will increase. Effect on defense will be lowered.
Other - May not be viable in the early game if the defense is decreased by a lot. Though loss of defense will be reduced later on, it must not exceed a 10% decrease.





Name - Tornado Slash
Effect - Deals 3 slash to the enemy at a rapid rate. It has almost 100% accuracy but damage dealt is low. The attack phrase will take 1s or less. About 5 to 6s cooldown.
Type - Physical
Changes Per Level - Damage increases, mana increases. Probably, when the skill reaches max level, it has a chance of increasing attack speed from using melee attacks.
Other - Damage is low in order to make up for the high accuracy and speed. Cooldown is so that they will not spam this skill and not give the enemy a chance to attack. By having another function at max level, it will give them an incentive to be of a higher level.


Name - Devastation
Effect - Summons two explosive shell with a small radius which damages unit in the affected area. Also, the closer they are to the centre of the explosion, the higher damage they receive. There will also be a chance that they will be afflicted with burns.
Type - Active
Changes per level - The explosive radius, damage and cooldown will increase gradually together with burns.
Other - Explosive radius must not be too high in case they take advantage. It can also be tweaked so that it can only be used when agitated have been casted.

Name - Call for arm
Effect - Summons 3 soldiers which will fight for you for a period of time. However, whenever they are on the field, the hero's hp will decrease gradually. If they die, they become spirit water which can heal a small amount of hp. Their stats are average with none of them being distinctively better ove another.
Type - Active Support
Changes Per Level - stats of the soldier and damage done to the hero will increase.
Other - It can be used as a skill for magic characters who are low in hp. They can use call for arm to use the soldiers as tank while the magic hero can cast spells which may take time.

Name - Duel
Effect - It creates an arena in which the champion and the targeted enemy champion are on a 1 v 1 fight, whether or not an arena is created on site or if they appear elsewhere. There will be no way for outside interference, and they are only released when one of them dies. Both of them will take a percentage of their HP damage. The enemy will also recieve an intimidated buff and be weaker.
Changes Per Level - The advantage the caster has
Other - May be a bit difficult to code to prevent outside interference.

Name - Last stand
Effect - The caster gains a major increase in attack and becomes immune to stuns, and will also have an extremely small increase in hp. However,the caster no longer naturally regenerates health and all non-lifesteal heals will be halved. Also, if all nearby enemies are dead, the caster will die and may also be subjected to increase respawn times.
Type - Physical
Changes Per Level - The attack will increase, and perhaps the hp increase.
Other - Should not have a short cooldown.

Stop.

You're going to make a mess if you just draw up a list of 400 spells. I guarantee it.

Firstly, 400. Assuming 4 or 5 spells per hero, you're making 80 to 100 heroes.

That is a lot. That, with a full design team, would take years, assuming you take the time to polish and stylise your heroes sufficiently. Making this many heroes in a shotgun approach runs the risk of producing poor heroes.

When developing a hero, you need to identify a few aspects prior.

What role on the battlefield will it fill?
What aspects of the hero will be satisfying?
What style of play should the hero promote?
What makes this hero different from the ones I already made?

These are tough questions, and are just as important as the hero's skill set.

To provide an example, let's say I'm creating an assassin character.

Her role will be to provide modest disables and high damage, while being fragile. This combination of attributes grants her a bonus when soloing another hero, while being disproportionately weak when outnumbered.

What would make her satisfying to play is her situational style of play. Getting a hero alone will give you an advantage. To aid her in this, she would need some intel style ability that grants vision or denies enemy vision. Successfully applying this intel to the battlefield and pulling off a successful kill is what would make her satisfying.

So. She needs some high damage skills, with moderate disables. She needs an ability to help her set up a kill, and a long cooldown, high damage ultimate would probably fit her best. Ability names are generic.

Strike
Deals x damage and marks the target for death. Each mark increases the damage you deal against that target by y%. Marks stack to 5.

This encourages you to stay on one target and commit to killing that target once begin. Her damage without marks would be below average, while at 5 marks, her damage would be unsurvivable.

Poison
Passive. Attacks slow the target by x% and deal y additional damage over 15 sec.

Can be activated to provide a% additional attack speed for b sec.

Basic cooldown and the moderate disable. Move speed reduction mostly to prevent her target from escaping.


Stealth
Her intel ability. Leveling could grant energy regen bonus or movement speed while active. Pretty standard RPG stealth. Alternatively;


Mark of Death
Places a mark on a target. You gain x% of the target's vision radius and can teleport to the target at any time, so long as the target is within y range of you.

This allows you to set up kills and provides the intel needed to properly allow you to wait until the enemy is alone. The mark should only be visible to the caster.


Generic High Damage Ultimate
Fill in whatever you want here. Ultimates should be high risk for the caster too. Either difficult to aim or forces the caster into a more vulnerable state.

Firstly, 400. Assuming 4 or 5 spells per hero, you're making 80 to 100 heroes.

I posted in this thread that i revised the number of skills to 100 regular with 50 ultimate skills. Also there are no set characters in this game. Without giving too much info about the game away, when you start this game you will be making your own custom hero based on the skills that are available to you. After the game gets a little farther into production i will post a link to some gameplay footage. Although i do appreciate your input on this issue

Name - Hidden in another
Effect - This lets the caster go into an ally champion, during which the caster is immaterial. This has a mana cost as well as a continuous mana cost. However, the caster will also give the host a buff. Moreover, the caster can still cast spells, although at a higher cost. Heals will apply to the host and only have half affect on the caster, and while inside the host the caster regenerates slowly. All buffs apply mostly to the host and are X% effective.
Type - Probably magical
Changes Per Level - How much the host benefits, what percent by which the buffs apply to the host, how long you can sustain it.
Other - Essentially intended for supporting another character.

Name - Amplifier
Effect - When used on an self or ally unit, it will increase the effect of spells being casted for 6 seconds. If used on an enemy, it will reduce the effect of spells for 4 seconds. Not applicable to magic heros.
Type - Magical
Changes per level - Effect increases and reduces effect by 1% each. Mana increases by about 10-20.
Others - This spell works as a support spell to enhance the effectiveness of magic spells and weakening when required. A useful spell to have for both defensive and offensive

Name - Lightning Dash
Effect - Electricity boosts the speed of the character setting him up for a powerful dash with electrical power of 2-4m before the electricity is lost. Any enemy that lie within the enemy dash will suffer damage and a low chance of being stunned for 2s.
Type - Magical
Changes per level - The attack, range and rate of stun will increase. Higher mana cost
Others - This spell works as an offensive spell which helps to close up to enemies and messes up the opponent team arrangement.

Name - Seal of the fragile soul
Effect - Summons a dark spirit which captures the soul of a player leaving him vulnerable to attacks for 3.4s. It requires 2.5 seconds before the spell is casted. If interfered, the caster will suffer 70 damage.
Type - Magical
Changes per level - The time in which the target is trapped increase as well as the damage the caster shall suffer if the spell casting process is interfered. Casting time reduces by about 0.05-0.1s.
Others - This spell is intended to be used as a trap spell which helps to temporary reduce the strength of the enemy forces. However, it will result in the spell caster being the primary target. On the side note, it could be used to bait the enemy as the enemy will pull all stops in disrupting the spell.

Name - Divine barrier
Effect - Summons 2 walls of 1.5m long. Player have to click on three spots. The point where they click will be the middle point of the wall. They can choose between vertical or horizontal walls. It will last for 6s.
Type - Magical
Changes per level - The time in which the wall will last and the length will increase.
Others - This spell is used as a offensive or defensive support spell. It prevents enemy from retreating and allows allies to retreat with ease.

Name - Sword Stance
Effect - Increases the damage dealt by the sword for 4 seconds. Speed however will be reduced slightly.
Type - Physical
Changes per level - The damage done will increase and the speed loss will be reduced.
Others - It is used as a support spell to self to increase performance during fight especially when it is a head to head fight where speed is not essential.

Name - Finisher
Effect - Deals 50% of the enemy total health to him. He must lie within 1.2m from the caster. At the same time, the caster will suffer a 30% loss in hp if the spell succeeds. Sword stance must be casted beforehand.
Type - Physical(Ultimate)
Changes per level - The distance range increases and health loss to self decreases.
Others - This spell is used as a finisher as the name says after allies have severely weakened the target.

Name - Grazing Protection
Effect - When casted, it gives the player a 15% chance to reflect enemy physical attack back to them. The spell will last for 6.8s.
Type - Physical
Changes per level - The chance of reflection increases.
Others - This spell can be given to a magic user who is weak against physical attacks. This ensures that they will not fall as easily to enemy fire.

Name - Trident Slash
Effect - When casted, the enemy will pierce the enemy with a powerful spear going deep into the body. It causes the opponent to bleed and deals dot damage for 6 seconds. There will be a 50% chance that melee heros will not bleed.
Type - Physical
Changes per level - Damage as well as dot damage increases.
Others - It is a spike spell which is used to 'snipe' particular enemies.

Hope this spells are of use to you. Good luck!

Name - Parry
Effect - When activated, if in the next X seconds the champion is hit, potentially including non-ultimate skillshots, it is negated, the opponent is stunned, and the caster of the spell gets a free hit
Type - Melee
Changes Per Level - The stun, bonus damage, and the convenience


Name - Feint
Effect - It renders the caster invisible and renders an illusion that the caster player controls. If any damage is done (although the illusion might actually gain a little bit of durability), the illusion dissapears, the caster gets a speed and attack rate bonus, and the person who dealt the damage is stunned. If the caster is harmed, the illusion is dispelled.
Type - Physical?
Changes Per Level - The durability and the bonus it gives to the caster


Name - En Guarde
Effect - It's a semi-passive. When activated, attacks will drain the "mana" of the player instead of health. However, the player is also slowed
Type - Physical
Changes Per Level - The efficiency is improved and the slow is decreased
Other - Essentially, it isn't what you want to use to escape


Name - Coupe De Grace
Effect - If this can deal enough damage to kill an opponent, it deals that amount of damage. However, if the enemy has more hp and wouldn't die, then you cannot use this spell
Type - Physical. Maybe ultimate
Changes Per Level - The amount of damage this can do
Other - I don't think it should have a small range

Personally, I'd concentrate on getting just a few easy skills working and then playtesting them. Once you get an idea how these simple mechanics work, and balance them it will be much easier to come up with the more complicated ones.

eg: Stun, Direct Damage, Heal, buffs, slow, frost arrows, flash / blink, poison / damage over time, a dodge/block.

Just throwing out some random ones. Once you've worked that out you can start comboing ideas together. Once you know a stun works as expected, you can do a skill shot stun. Once you get a feel for how a slow works you can add a speed buff for the caster ("Steal speed" style thing in a few MOBAs). If Blink works, try a 'blink strike' (teleport to enemy then do a high damage attack).

I think you'll find this process easier than trying to balance hundreds of skills at the same time, all of which would be based off the same few mechanics.