Greetings! first-time poster here. I found this game a few days ago on my recommended list and fell in love. Though so far, I've actually only played the demo, as I'm unable to drop the money for the full version right now. But I have seen videos of the whole thing and consulted the wiki. I'd really like to add to this discussion by giving my own ideas for support skills. I apologize in advance, this is going to be a long post.
First, I wanna say, since the topic has come up, that I love playing support roles in multiplayer games. I genuinely find it fun. It's hard to explain why exactly, but the gist of it is that there's great satisfaction to be found in helping others succeed. People also tend to heap much adoration and gratitude on good supports so there's that.
I've gathered that the whole support skill page itself is a placeholder, but I thought up ideas that fit the format anyway just because. Also, all these ideas hinge on two important factors:
1.) The same skills from different players do not stack. Only the highest effect applies. I don't know if it's like this already because I have not tried multiplayer. The power of these skills also does not depend on any stats, just the skill level.
2.) A solution to this problem:
You gotta think of the poor guy that chose to play support when it came to multiplayer. When their friend(s) decide they have other games to play or another meeting time can't be arranged, but they reeeeaaally want to continue playing their character, what are they going to do? If their skills are weak in SP because they're balanced towards multiplayer then they basically have to start over.
From my admittedly limited experience with modern MMOs, putting a price on SP refunds is an outdated practice. Most don't do it, and it doesn't break game balance as long as total SP is still limited. If SoG did this, this problem would be solved. It has an added bonus of allowing players to try whatever until they find a build that suits them. Some might say that being able to change your skill build on the fly would be overpowered, but it is really? I find that most don't bother. They just find it comfortable to just stick with one build. All the required menu navigation alone is enough to deter most players from resetting willy nilly. But even if they do constantly switch, so what? It's not much different than switching your equipment to suit the situation, which they'd likely have to do as well. Also, it's obviously unwise to do so mid-battle, at least in multiplayer.
All that said, I'm fine with SP refunds coming at a cost in SoG, But I do wish it wasn't so costly. I'd say a flat rate like 50 gold per skill point would be ideal. With that out of the way, onto my actual skill suggestions. And just a forewarning: I'm bad at coming up with names.
Offensive skills
Amplify damage - Casts like Meteor and Earth Spike. Marks enemies with a debuff that makes them take a per-skill-level percentage of amplified damage.
Bronze charge increases area of effect. Silver charge gives more area and further amplified damage. Gold charges gives more area and doubles duration.
I think such a spell would work wonderfully in SoG. G-meister made a similar suggestion earlier, but I don't think it needs to be nearly so complicated. If an enemy takes 10% more damage for example, it doesn't matter if one or eight people are wailing on it, it still takes 10% more damage. Screens are often filled with mobs, as such this spell is limited by it's AoE. As boss battles take a while, it would then be limited by it's duration.
Dark swamp - Also casts like Meteor and Earth spike. Creates a swamp at target location that lasts for a while. enemies that step into it have their movement and attack speed slowed based on skill level. Only one swamp per player. Casting a new one will delete the old. Also does not affect flying enemies.
Bronze charge increases area of effect. Silver charge increases swamp duration. Gold charge adds a suction effect that pulls enemies toward the center.
This skill would be real nifty for a "siege defense" so to speak or when trying to run away. If it can be implemented, the suction effect would be super useful offensively.
Thorns - Buffs the user. When attacked, the enemy also takes damage based on skill level. Returns damage even if the attack was blocked by a shield.
Bronze charge buffs nearby allies as well. Silver charge increases area and duration. Gold charge turns the recoil damage into an AoE centered around the attacker, also deals great damage upon the buffed ally's death.
Actually, perhaps this one skill should be based on ATK or MATK, or both at once.
Passive skills - These probably should just max at level 5 or something.
Crowd control - Pulls aggro toward/away from you. Can toggle between attracting or repelling enemies... somehow. Leveling increases the Area of Effect, and at max level it decreases the frequency of enemy attacks.
Quite useless in single player, but again, if skills weren't so costly to refund, this wouldn't be a problem.
Pain Split - If a nearby ally takes damage, 30ish percent of that damage is transferred to you. Leveling increases area of effect, and at max level, if you or an ally take fatal damage, the effect is dispelled for a time and they survive with 1HP.
Again, quite useless in single player.
Extension - Debuffs on nearby enemies gain increased duration. Buffs on nearby allies gain increased duration. Leveling increases area of effect. At max level, if you cause a debuff on an enemy, it spreads to all enemies in an area around you. Perhaps this effect would have a cooldown.
Defensive Skills - I think the current ones could use a tiny bit of tweaking. Especially when it comes to duration.
Protect - Create a barrier around yourself which increases your armor.
Bronze charge further increases your armor and affects nearby allies as well. Silver charge increases area and duration. Gold charge further increases armor and allows players to take one more hit while charging/using a skill and not get interrupted.
Haste - Increases attack and cast speed.
Bronze charge increases speeds and affects nearby allies as well. Silver charge increases area and duration. Gold charge further increases speeds, grants a movement speed buff as well, and allows you to auto-fire normal attacks.
As far as I can tell, nothing in the game thus far buffs movement speed. Why is this? This should happen here.
Healing Aura - I've saved the best for last, the hotly debated topic of healing. I actually made an adventure game myself in which this very same problem arose. I just decided to go with a gradual regeneration thing and I think the same thing can work in SoG. This skill would block of a portion of your EP for sustained health regeneration. The key is to make the regen very slow, such that enemies can easily out damage it, but the player can still benefit as long as they don't get hit. In fact, it could be made so that the regen stops for a bit when hit. Also it regenerates at a flat rate, not a percentage so that it would become rather useless if you don't level the skill. This would hopefully keep this skill from feeling essential. If you don't have the SP to go all the way, then it's not worth it. This wouldn't break boss fights as there isn't any places to camp out during them, at least as far as I'm aware. Players could camp out and heal while "dungeoning", sure, but they do that anyway really, just with potions.
Bronze charge would make it affect nearby allies. I'm thinking in a relatively small AoE. Silver charge increases the area. Gold charge buffs EP regeneration rate as well.
Alas, I do not know how to balance this for Arcade mode. I would just disable it, personally.
Optionally, it could be made into a debuff that allows players to leech life when they damage/kill marked enemies. This would mean the more players there are, the more the more the health gain would be divided. This also makes it so you have to engage in combat if you want to heal. Risk and reward. But probably still couldn't work in Arcade mode.
Of course, if that still doesn't work, there's that idea Teddy mentioned. I would make it work like so:
Barrier Bubble - Casts like Meteor. Creates a bubble at target location. For all allies inside the bubble, the bubble will take damage for them, until it runs out of HP. Enemies and allies can move freely inside or outside the bubble, and the bubble does not move. Only one bubble can exist at a time. If another player casts one, the old one is destroyed. Perhaps EP is blocked until it's destroyed.
Charging could add effects like detonation upon depletion, or slightly buffing those who step inside it.
Many games have a skill like this. But I'm mostly thinking of this one:
.
If you read all of this, thanks. I just wanted to get all this out of my system.