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UPDATE!
Link to Post on Blizzard Forums - Please go Support the Idea (Goal is to get a Dev response)
Spell In Action! (With NEW pictures!)
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Thanks to a very talented Mr. Outcast01 at SC2Mapster Forums, the spell is now a Work in Progress!
DO NOT FEAR those Siege Lines any longer!
![[image loading]](http://i.imgur.com/CxCe3.jpg)
Smoke OUT! (Now in range of enemy tanks, but no shooting yet

![[image loading]](http://i.imgur.com/Jdtxe.jpg)
Smoke out again, leap frog to get even closer. Knock Knock Siege Line. (No damage taken yet, imagine if you didn't have Smoke Screen Shells)
![[image loading]](http://i.imgur.com/xB6ac.jpg)
Siege Line No More. *Note friendly Raven giving vision this whole time, stressing the importance of vision, whereas red didn't have any.
![[image loading]](http://i.imgur.com/BqIaY.jpg)
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Test Map
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I've made a very rudimentary map to test the idea of using LOS blocking in big battles. And it is VERY COOL. The dynamic is awesome. You never know what's lurking on the other side of the smoke. Here's the map: Smoke Screen Shell Test Map
Open map in editor, then click the Test Map button. It should load and say you've Won or it's a Tie. Ignore that, and click Return to Game. Change game speed in gameplay menu to suit your needs.
Scenario 1: In the middle of the map, you have 3 armies, A-move them to the LEFT. There is a siege line behind the smoke. This simulates blue's defender's advantage using Smoke Screen Shells.
Scenario 2: You have a group of unsieged tanks. Use them to lure the Zerg army that's to your right by attacking, then run to the left behind the smoke, leading them into a trap. You can always use your Orbitals to gain vision for yourself.
Until a more skillful mapper/coder makes a better version of the map, this will have to do. Enjoy.
Open map in editor, then click the Test Map button. It should load and say you've Won or it's a Tie. Ignore that, and click Return to Game. Change game speed in gameplay menu to suit your needs.
Scenario 1: In the middle of the map, you have 3 armies, A-move them to the LEFT. There is a siege line behind the smoke. This simulates blue's defender's advantage using Smoke Screen Shells.
Scenario 2: You have a group of unsieged tanks. Use them to lure the Zerg army that's to your right by attacking, then run to the left behind the smoke, leading them into a trap. You can always use your Orbitals to gain vision for yourself.
Until a more skillful mapper/coder makes a better version of the map, this will have to do. Enjoy.
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Common Questions Addressed:
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Thanks for all the responses, positive and negative. Allow me to address some of the most common questions or confusions:
1) "Obs, scan, flying building or air units completely negate this ability."
Yea, this ability was designed with these counters in mind. The key to being successful is to catch your opponent off guard with it. With a quiet sound effect (since it's smoke not explosive), your opponent will be forced to keep their eyes on their armies and not just macro. In addition, this ability requires air superiority and it is not equally useful in all MUs. It was mostly intended to help break Siege Lines.
2) "This is confusing and bad for spectators."
Don't underestimate the intelligence of spectators. Game Observers can always switch between the visions of two players or explain the ability. Since Smoke Grenades and Screens are existing in the real world used by real militaries, I don't see how it would be more difficult to explain than say Graviton Beam. Plus, we already by LOS blockers on maps, and people seem to get it fine.
3) "It is like Dark Swarm, Optical Flare, etc."
You are somewhat correct because these spells all manipulate vision. However, Smoke Screen Shell is unique because it only blocks lines of sight and can be used by both players depending on who has vision on either side of the smoke.
4) ***IMPORTANT: Still pictures cannot show the dynamics of this ability. You must use your imagination. The screenshots only show one instant MOMENT during the battle. In theory, the Smoke Screen Shell may negate sight for its entire duration, but in PRACTICE, that's rarely the case. It is meant to buy you time. Reduce 1 or 2 volleys of shots from incoming tanks. Sometimes that's all you need. For example, of the 15s of duration, you may actually have 5s to move or get close before your opponent realizes what is happening and scan. Or your Siege Line may get a short, but precious, 7s (enough to get 1 or 2 extra shots off) of free reign over an assaulting enemy Protoss or Zerg army before their spotting Observers or Overlords reveal your tanks that are behind the smoke. Another example, if a Zerg is crafty he'll make you think he doesn't have vision but had already placed a burrowed infestor under your army, rendering any Smoke Screens useless. Remember, just because a spell lasts a certain time, it doesn't mean that it is effective for that amount of time (e.g. Storms can be dodged, etc.) ***
I hope you will try to read the entire thread before posting because it is likely that your concern has already been addressed and covered. Perhaps someone can enlist their Galaxy Editor expertise and make this so we can see a video of it in action or have play tests to determine it's viability.
1) "Obs, scan, flying building or air units completely negate this ability."
Yea, this ability was designed with these counters in mind. The key to being successful is to catch your opponent off guard with it. With a quiet sound effect (since it's smoke not explosive), your opponent will be forced to keep their eyes on their armies and not just macro. In addition, this ability requires air superiority and it is not equally useful in all MUs. It was mostly intended to help break Siege Lines.
2) "This is confusing and bad for spectators."
Don't underestimate the intelligence of spectators. Game Observers can always switch between the visions of two players or explain the ability. Since Smoke Grenades and Screens are existing in the real world used by real militaries, I don't see how it would be more difficult to explain than say Graviton Beam. Plus, we already by LOS blockers on maps, and people seem to get it fine.
3) "It is like Dark Swarm, Optical Flare, etc."
You are somewhat correct because these spells all manipulate vision. However, Smoke Screen Shell is unique because it only blocks lines of sight and can be used by both players depending on who has vision on either side of the smoke.
4) ***IMPORTANT: Still pictures cannot show the dynamics of this ability. You must use your imagination. The screenshots only show one instant MOMENT during the battle. In theory, the Smoke Screen Shell may negate sight for its entire duration, but in PRACTICE, that's rarely the case. It is meant to buy you time. Reduce 1 or 2 volleys of shots from incoming tanks. Sometimes that's all you need. For example, of the 15s of duration, you may actually have 5s to move or get close before your opponent realizes what is happening and scan. Or your Siege Line may get a short, but precious, 7s (enough to get 1 or 2 extra shots off) of free reign over an assaulting enemy Protoss or Zerg army before their spotting Observers or Overlords reveal your tanks that are behind the smoke. Another example, if a Zerg is crafty he'll make you think he doesn't have vision but had already placed a burrowed infestor under your army, rendering any Smoke Screens useless. Remember, just because a spell lasts a certain time, it doesn't mean that it is effective for that amount of time (e.g. Storms can be dodged, etc.) ***
I hope you will try to read the entire thread before posting because it is likely that your concern has already been addressed and covered. Perhaps someone can enlist their Galaxy Editor expertise and make this so we can see a video of it in action or have play tests to determine it's viability.
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Main Thread:
For HOTS, Blizzard is experimenting with ideas to help Terrans break siege lines. Their answer right now is the Warhound's missile pack. But the ability itself is quite straight forward and not very interesting to watch. Of the many new elements of SC2, I think the most underrated one is the manipulation of unit vision. The LOS blockers on maps are interesting, but what if this concept were made into an ability?
New Siege Tank Ability - "Smoke Screen Shell"
-Basically works as a temporary LOS blocker (lasts 15-20s) *all figures are tentative
-Fired from Siege Tanks on a cool down (30-60s)
-Can be used offensively and defensively
-Works like current neutral LOS blockers on maps
-The ability itself doesn't grant you vision. You need vision to fire it at full range. You need vision to see past friendly or enemy Smoke Screens.
-The ability does NOT require research. It is automatically given to Siege Tanks in both modes and can be used in both modes, albeit with different ranges depending on modes. Sieged mode (2-13). Unsieged mode (7).
This ability FITS the lore and style of the Terran race. Terrans emphasize army positioning and movement. This ability gives the Terran army that power. Smoke Screen Shell works like modern smoke grenades, smoke artillery rounds or tank smoke dispensers. The purpose of smoke is to cover troop movement, in advance or retreat. (0:46 of video)
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Or
Attack:
Launch some Smoke Screen Shells ahead of your army to block vision so you can get close without taking damage. (Yes, those LOS doodads are placeholders, but they simulate the size, shape and effect of the final ability). *This is the observer's POV. Red (you) still need to gain vision in order to actually attack/shoot Blue (enemy).
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![[image loading]](http://i.imgur.com/Kvklg.jpg)
What your enemy sees (or don't see

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![[image loading]](http://i.imgur.com/yVnYC.jpg)
*Also I know the pictures kind of look weird because the units aren't facing the right directions, but I'm not good at using the editor and everything is a mock up. So for now, there are arrows.

Defend:
If your enemy is attacking into your Siege Tanks, launch smoke rounds nearby to block their vision. Like the placement of forcefields, you can use multiple smoke screens to make a larger shape of wall, aligned or staggered. Unlike forcefields, units can walk through.

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![[image loading]](http://i.imgur.com/bYNAi.jpg)
This is the POV of the advancing Protoss Army. One cannot attack what one cannot see. Protoss would need to be creative. Send in an observer, keep it from getting sniped. Or run a unit in front of the main group.
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![[image loading]](http://i.imgur.com/KSEoC.jpg)
In Retreat
It's a TRAP! Scenario: Use retreating Siege Tanks to bait Zerg army into a trap. Launch Smoke Screen to conceal your retreat and prevent zerg from seeing the Terran trap, much like burrowed Banelings, except you are hiding an entire army. (Green indicates retreat and Red indicates attack). *Note the different angles and shapes you can form from shooting smoke from different angles.
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![[image loading]](http://i.imgur.com/zJeaA.jpg)
What the Zerg would see. Smart players could use this as a double fake, feigning a trap so that their tanks will survive.
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![[image loading]](http://i.imgur.com/6mVqX.jpg)
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I made that in editor, but I'm not a coder. If you guys think this is something interesting enough to be explored, then maybe someone who is more experienced with the coder can make this ability and prove this concept.
Here are some tentative "prototype" test attributes:
Range: As far as Siege Tanks can fire
Duration: 10-15s (Enough time for tanks to Unsiege after using Smoke Screen, and attack with main army)
Cooldown: 30-60s (Short enough to be reused for dynamic movement, but not enough to be spammy at the same time)
Approximate size of the ability compared to other units.
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![[image loading]](http://i.imgur.com/ATtwa.jpg)
- Works like any other LOS blocker. The enemy can gain vision with all the regular ways to gain vision on map, such as scans, obs, air units, etc.
-Ability can be used in both Sieged and Unsieged mode, but range will be reduced to the range of Unsieged Tank in Unsieged mode (like real-world tanks)
-The line of smoke is always perpendicular (90 degrees) to the direction of firing. Multiple tanks can fire rounds in combination to form larger Smoke Screens of different shapes.
- Launches like a missile, flies like a projectile, meaning the Shell doesn't get to the target area instantaneously (but still fairly fast, like EMP from Ghosts). This gives both you and your opponent enough time to either regroup or react.
- Makes a distinctive, but soft, sound effect so that you know the ability is being used even if you or your opponent is not watching the army. This allows time for players to react.
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Please give your constructive feedback. Perhaps help me think of some gameplay implications this will create (I will add to OP).
Gameplay/Misc. Implications:
- Frees Warhound to do an Anti-Air role again. Thor can be removed.
- Unique Ability that is interesting and dynamic to watch.