I shall elaborate each proposed skill for the proposed class of Helio'Noths. Take whatever skills you like and apply them. If you don't like a skill, don't use it. That's why I added more than the average 4 skills.
Stalker (Like I said, an AGI based unit with tricks from assassinating to scouting, great for PVP)
Hide in Shadow: So long as the hero does not move, he shall remain invisibile indefinetly. However, when hiding in the shadows he will take 80% more damage from physical attacks, while dealing 3 times his AGI if sneak damage occurs. Vulnerability to physical attacks can be reduced by his AGI stat down to 38%.
Subterfuge: While under Hide in Shadows, activate this skill to Slow Walk while slowly draining your mana. Each second under subterfuge has a chance to break your invisibility determined by your INT.
Unseen Presence: Make your presence felt while invisible, but not seen. Reduces damage, armor, and movement speed of enemies in a medium radius based on INT + AGI / 2. (Can opt to add chance to critically damage enemies and chance for enemies to miss if you so desire.) *Choose if it's a channeled skill/aura/activated.*
Sight Marker: Gain shared vision of the unit while slowly causing damage over time to it.
Cornered Retreat: When less than 20% HP to 45% HP based on AGI stat, the unit can rush through enemies, dealing damage in a line as it passes through them.
Retreat on Sight: If attacked while hiding in shadows, the unit will split into a bunch of images all over a random area. Works like phase shift, only with mirror images that last for about 1-4 seconds.
Recuperate in Shadows: The stalker will regenerate HP much quicker so long as no enemy units are in the area to cause him worry. Based on INT+AGI/STR.
Dark Magician (A mix of a minor healer/buffer with potent Damage Dealing. Makes the most use of INT, but needs a concious amount of STR too)
Dark Epsilon: Double strike based on INT. The first strike is initiated with the spell's casting. The second strike will only be initiated if the enemy goes up to a level 5 Paling Touch within 5 seconds of casting Epsilon. The second strike will consume and be amplified by Paling Touch's 5th level.
Paling Touch: Each hit with your normal attack will imbue an enemy with Paling Touch. The base Paling Touch level the enemy starts with is determined by your total STR. (Example: For STR 1-25, LVL 1; 26-45, LVL 2; etc.) And each hit after the first will increase the counter by 1.
When the Dark Magician casts a spell on an enemy with Paling Touch, the spell damage is amplified based on Paling Touch's level. Paling Touch is then reduced to 0 on the enemy. The only exception of this is Dark Epsilon, which will be amplified only by 1 level, and reduce Paling Touch by one level. (This will help ensure that the player must hit the unit at least one more time before Dark Epsilon's second hit comes off)
Paling Touch's debuff level cannot exceed five, and wears down by one level every 5 seconds.
Pale Ent/Daemon: Has something to do with your Daemon. Dunno, don't really understand how Daemon's work.
Villify: Causes unit to rot from the inside out. Strikes with an initial hit based on INT, then DOT damage that's a percent of the initial strike.
Dark Token: When the Dark Magician casts a spell he has a small, STR based chance to create a Dark Token, which will replenish 3% HP and 2% MP but cause a 2 second silence and has a CD of 10 seconds. Tokens stack up to 3 and can be given to allies. If there is no room in his inventory no tokens will be created.
Dark Gift: Combine 3 Dark Tokens to create a Dark Gift. Costs 9% HP and 6% MP plus a base MP cost to create. Consuming a Dark Gift gives a random buff from a pool of blessings.
Cover in Shadow: Generates 1 Shadow on an ally or enemy, max of 3. The next time a Token is consumed, it will damage any enemy with a shadow for the amount of HP and MP recovered by the consuming hero and heal MP and HP on allies for the amount recovered, multiplying that amount by the number of shadows on the enemy. Cooldown is five seconds, duration based on INT + STR/2. So long as the shadow is up, minor attack speed is reduced on the unit.
Mark of Helio: The Mark of Helio can be an actual skin mark, a design, a banner, whatever would work for those of the Helio race and their leader. This union will disperse the damage recieved amongst the Helio'Noth, and reduce the damage based on how many Helio are present in an AoE. AoE based on INT, reduction bonus gained with multiple Dark Magicians.
Pale Presence: Those in the presence of the Dark Magician will lose Mana. All mana lost from Pale Presence will regenerate the Dark Magician's.
Dark Wight (Tankers who excel with Max HP and STR stats at their highest. Can yield a suitable amount of damage as well.)
Envelop: Cast while attacking a unit to Envelop them in a ghostly light. The light does damage based on STR.
Over-Take: While the damaged unit is enveloped in ghostly light, cast this on them to transform them into an immobile Wight with the Banish effect. If hit with a spell, the Wight will break it's ghostly bond and return to normal prematurely, but not until the damage has taken place.
Helio's Will: Set to carry out the establishment of their race, Helio's Will grants them a max HP boost based on other Helio'Noths in the area. Area based on STR.
Grim: When low on HP, the Dark Wight is ready, remaining calm and placid on the surface while faced with a Grim outlook. Causes the Dark Wight to Taunt while amplifying damage on him for 2.2 seconds. At the end of the duration, he releases a brutal shockwave that deals damage based on the difference between current and maxHP in an AoE based on STR.
Ghostly Presence: Any unit that starts to attack the Dark Wight has a chance to be struck with a ghost. The Manifestation will last until the unit changes targets. So long as the ghost remains, the unit will deal only 75% damage to the target and slowly lose HP. Chance based on STR, HP lost base on damage dealt.
Pale Shadow: Creates a doppleganger of the Dark Wight, which will mimic his spells and actions. However, the Pale Shadow only has a fraction of the Dark Wight's stats, and so does reduced damage.
Walking Dead: When killed, a Walking Dead unit is created, which will fight in place of the Dark Wight until he is ressurected. It's HP is based on the Wight's STR, it's damage based on AGI, and mana based on INT. All Walking Dead can taunt. However, if the Walking Dead is killed, a penalty is deduced from the Wight.
Intimidate: Has a small chance every seconds to send a random enemy unit running. The distance ran is based on STR and the chance based on HP Lost. Can be turned off with the command -intimidateon/off
Anyways, for names, I'm trying to concieve something far more unique than "Warlock" "Necromancer" "Warrior" to keep your RPG feelign original and the lore feeling fresh. Certainly a name like Bonegrinder would be a bit better than Bonecrusher.
Anyways, I'll see if I can't hit your themed ideas a little more on the head.