EPT
Splash and Area of Effect Damage in Starcraft
![[image loading]](http://us.media.blizzard.com/sc2/media/screenshots/protoss_colossus_002-large.jpg)
Key:
Allied units: my partner's units
Friendly units: my units
A key element of balancing starcraft is determining how much splash damage a unit can do, how it is calculated, and how it affects friendly and allied forces. I'm going to summarize some of my thoughts about how this worked in sc1 and compare it to sc2.
Spells
Let's go through the spells in sc1 that did splash damage including area spells (realistically I don't think any spells do 'splash' per say, but you get what I mean). I'm doing this from memory so I probably won't get everything perfectly (feel free to identify corrections).
1. Psionic Storm: deals a lot of damage over a given area (equal dps anywhere in this region, armor ignored), spread across several seconds. Can damage allied and friendly units.
2. Irradiate: deals a lot of damage to a biological unit over a long period of time (or until it died) plus deals equal damage to any closeby biological unit. Can damage allied and friendly units.
3. EMP: deals full shields damage to a small area, and saps all energy.
4. Plague: deals a lot of damage to a given area over a long window of time, but can't bring the unit to 0 hp. Can damage allied and friendly units.
5. Nuke: Huge amount of damage to a large area. Often difficult to successfully land the nuke without losing your ghost. Buildings receive 2/3 damage, even if they have much higher hp than the typical nuke damage to units.
Now for the spells in sc2:
1. Psionic Storm: similar in nature to the sc1 equivalent. The size of the area and damage output/rate can be modified to balance as necessary.
2. EMP: very similar in nature to the sc1 equivalent. The size of the area and range of casting can both be modified to balance.
3. Heat seeking missile: deals damage to an area if the missiles strikes the target. Damages allies and friendly units.
4. Fungal Growth: Certainly reminds me of plague. However, it also makes the units unable to move for a short time. I think the total damage dealt to high-hp units is much lower than with plague, but the spell in many situations is much more effective on groups of low-hp units. Fungal growth can be used at 'tier 2' unlike plague which required 'tier 3'. Fungal growth is a beast.
5. Nuke: Very similar to sc1... someone can point out to me if there are any major differences.
Spells don't seem that different in sc2 compared to sc1. Plague was slightly buffed in some applications, and terran lost irradiate but gained heat seeking missile. P's main spell is still storm.
Units
Let's go through the units that deal splash or area damage in sc1.
1. Firebat: damage to a small area in front of the firebat, only worthwhile vs small melee units like lings/zealots or occasionally when assaulting sunkens due to their higher hp/armor than marines. I believe firebats will deal damage to allied units who get too close.
2. Sieged Tank: Deals 70 damage to primary target, and reduced damage to nearby surrounding units (including allied or friendly). Tanks always deal less damage to smaller units and more to larger units.
3. Valkyrie: Air to air damage that affects a 3x3 area. Deals damage to allied units.
4. Spider mine: Deals a lot of area damage! Not really a unit but I'm not sure how best to classify this.
5. Lurker: Damage in a straight line, range is pretty good. Requires lurker to be burrowed so it can't move until it unburrows. Deals damage to allied units but not friendly units.
6. Mutalisk: Damages 9 to the primary target, 3 to a nearby enemy target, and 1 to a third target.
7. Infested terran: deals huge damage to an area as it suicides. will hit allied and friendly units.
8. Archon: Deals 30 damage to primary target then a few points of damage to other units near the target. Splash will damage allied units.
9. Reaver: Deals a lot of damage to the primary target and equal amounts to enemies or allies near the target, and also deals reduced damage to units slightly further away from the target (I think, reavers are a bit weird).
10. Corsair: Air to air damage that is small to the primary target but frequent and deals some splash to surrounding air units. Splash will damage allied units.
How do these compare to sc2?
1. Hellion: deals damage in a straight line, is more effective vs light units. Sort of like an overpowered firebat riding on a vulture. Does this deal damage to allies?
2. Sieged tank: deals damage similarly to sc1 tanks. Yes it includes allied and friendly fire.
3. Thor: deals air splash to units near primary target. Not sure if it damages allies.
4. Mutalisk: I think it's the same as sc1 more or less.
5. Baneling: Works similarly to an infested terran from bw but on a smaller scale. Does not deal damage to allies or friendly units (I think). Deals damage even if killed before reaching target.
6. Ultralisk: Deals area damage now to all the units in front of it unlike in broodwar. Not sure if it hits allied units.
7. Colossus: Deals area damage in a line parallel to the enemy's concave (usually and this is effective). Has a large range that can be upgraded to 9. I don't believe it deals any allied damage.
8. Archon: Similar to sc1 damage (slightly lower).
I do need to check on a few of these sc2 units to see if damage is dealt to allies or not, but in general the trend seems to be less friendly and allied fire in sc2 than broodwar (not sure if I like this).
One unit in particular that stands out to me is the baneling. Its enhancements over the infested terran seem somewhat unchecked. It can deal damage even if killed before reaching its target, and doesn't splash friendly units. Those two sorta have to go hand in hand otherwise banelings would be too weak. However, a group of banelings can all reach a group of bio or other ground units and each detonate ideally without influencing each other (try that with infested terrans lol). What would seem logical to me is to make it so banelings that are detonated prematurely do not splash friendly forces (for fairness) but banelings that detonate when commanded to or when meeting an enemy troop deal a small amount of splash damage to nearby friendly units (much less so than the enemy). This would make sense when you consider that zerg could have an innate ressitance to the corrosive attack of the baneling, but not an infinite one. It would force the zerg to be careful not to deplete any banelings on friendly fire without greatly reducing the utilitize of banelings. Just a thought. I'm not going to make a claim that current revision banelings are OP/imba since I'm not qualified to.
I think an important part of balancing sc2 is to look at the spells and units above and see how they've changed from broodwar (a very well balanced game) to sc2 (a game currently being balanced at higher levels). Every change needs to be explained in the context of other aspects of sc2 besides splash that are different from sc1. It's too easy to compare a unit or spell from sc1 and see how it was apparently buffed/nerfed in sc2 and start complaining, but that new unit plays a different role in the new army of sc2. The mechanics of the game also work a lot differently including vision, roles of cliffs, fighting up ramps, etc. But, it's these types of units and spells that I believe determine more than anything else how excellent an RTS can be. They are also one of the main reasons why games like SC are so damned difficult and time-cosuming to balance.
If anyone can clear up any of the questions about which units do or don't deal friendly/allied damage or if you can point out errors I would appreciate it.
