Heres a cool idea for a unique ability for the fire lord.
Inferno furnace
The firelord removes all control over his firey body leting it split into orbs of fire which travel around burning everything in their path. The orbs burn everything they come into contact with, using it as fuel to become ever strong and hotter. As fire has no real physical manifest, they can only really be damaged via magical attacks. After a while the orbs will regroup and respawn the firelord.
Basically the spell is simlar to that of the panders ultimate but with different mechanics. The number of orbs spawned and their power depends on the hitpoints of the firelord and level of the spell. The duration of the orbs is based on the ammout of mana the hero had when cast and spell level. All mana of the hero is removed while the spell is in affect and and regeneration of the hero can not alter the hitpoints and mana he has after the spell ends.
These orbs move around burning all nearby hostile units or destructables, gaining power in the process of burning. The damage they inflist per second to destructables and units when burning them is based on the orbs power. The orbs lose power at a certain rate when not burning anything. Once exceeding a certain ammount of power (based on the power the orbs would have when the hero was at full HP), each orb will split into 2 equal sized orbs.
The orbs move around randomly towards anything burnable but stick together in a flock (never wondering too far from the center of the flock). The center of the flock can move inorder to folow retreating enemies or advancing fronts but is not controlable. If there is nolonger anything burnable nearby, the duration of the spell will degrade more rapidly until it is forced to revert to prevent excess power loss.
The orbs movements are not easilly controlable (dependswhat you feel but with trigger based movement even though they will be selectable they could not be moved) however they can be targted. The orbs can not be killed in conventional ways as their hitpoints are near infinite, however all damage delt to the orbs is relayed to their power, weaconing the orbs. The orbs have huge resistance to physical attacks taking only 25% or less of all attack damage dealt to them based on level (I advise evasion for this maybe with reasonable armor). The orbs however take full damage from spells, and so are best countered with them. If the power of an orb falls to 0, or spells capable of instantly killing units are used on it (if you have any), it will die. If the last orb dies, then a instant death ammount of damage is relayed from the killing unit directly to the hero (which should be hidden), instantly killing it and the spell ends.
If the duration expires, all orbs should regroup in the centre of the flock and reform (unhide) the hero. The curent hitpooints of the fire lord become that based appon the sum of power the orbs had (if the hero was at 50% hp and then the orbs doubled their initial power, then he will respawn at 100% hp). Any excess power which exceeds the maximum hitpoints of the fire lord will be converted into AoE damage to all enemies around where he reformed. The firelord will also be refunded part of his mana that was used in casting the spell, based appon the actual duration of how long it lasted (if it ran out of stuff to burn and ended faster he will be refunded more mana) and how much damage the orbs inflicted in total (less damage = more mana refunded).
I would guess that this would be an ultimate ability spell due to its potential power. I also garuntee you its 100% orignal combining many previous ideas with new mechanics into something new.
