I believe Starcraft 2 is one of the greatest games of all time. Despite being a decade old and now free-to-play this game still has a massive following online especially in Korea where they have international tournaments with big money cash prizes. Hell, even Starcraft the original still has a lot of people playing it.
I love Starcraft 2 and will return to play it on a regular basis despite having finished all the missions many times. This game has wonderful replay value even if you already know exactly what is going to happen on various missions. On some of the missions there are optional things that you don't really need to accomplish in order to advance but some people, like me, do it anyway.
One of the most fun missions to do this on as the Terrans is a level called "The Dig." This is the 9th mission as the Terrans and this mission is where you "unlock" the famous siege tank, which is a favorite unit of basically anyone that has ever played the game.
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In this mission you must gain control of a laser drill in order to open a temple door to gain access to a Protoss artifact. This is the only mission that I can recall up to this point in Starcraft where you gain control of something that you can not actually create and you never see this item ever again. The laser drill (pictured above) isn't just a drill to open the door to the temple though, it can also be used as a hell-powerful weapon against invading waves of enemies.... Well, if you can control it. This is one big complaint that people have about this thing as it can sometimes be a bit non-responsive unless you click just perfectly.
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While the only thing you are required to do with the laser drill is to open the temple door, which it will fire at automatically all the time anyway, it can also be used to destroy various statues, of which there are 3 I believe in order to get research points that will powerup your units in a variety of ways.
The map looks like this with the laser drill being in the middle
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If you wanted to simply get through this level as quickly as possible you wouldn't bother with making a forward assault on any of the 3 Protoss bases that exist, two to the north and one to the east. I think that most people when they go through this the first time would just establish a wall of siege tanks defending the drill along with some turrets to defend against flying units and then just let the drill do its thing opening the door. It isn't a tough mission honestly. However, the Protoss attack waves will not stop coming from the Protoss camps throughout the mission and while these waves are quite easily dispatched once you have a massive legion of siege tanks, it can be a lot of fun to do something that you perhaps weren't intended to do and completely wipe out the Protoss camps rather than just defend against them.
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I think that many of us have felt the urge to produce an overwhelming amount of siege tanks and make a forward attack seeing as how once the "fog of war" reveals the area ahead of you the siege tanks will make quick work of anything on the ground in front of them. If you bring a squadron of around a dozen siege tanks and perhaps 30 marines with nurse support, you can basically take out anything. The only thing that can go wrong is if the marines get too ambitions (which they tend to do) and move too far forward and get suicided by their own friendly fire in the form of siege tank "splash damage." If you do this properly though, and are able to get your tanks up those ramps and park them inside the protoss base, the enemy doesn't stand a chance.
This is easier said than done though because while you are doing your forward assault, the other 2 bases continue to attack from the other side, so you must remain vigilant and aware of these attacks so that you don't end up accidentally leaving your base wide open to a counter attack.
The laser drill is very useful in clearing out a base once you have revealed the area and once you have cleared out all existing troops you can probably just leave a couple of siege tanks and all the remaining marines and then just use the laser drill to destroy all remaining buildings. It makes quick work of them.
Another thing you have to keep in mind is that anytime you are not controlling the laser drill it will go back to working on the temple door and while this sounds great that it does that on its own, you don't want to destroy the gate too early because it will not leave you enough time to eliminate all the Protoss structures.
It can be a bit challenging to pull this off and you almost certainly will get frustrated with your units especially the siege tanks that have a tendency to completely block the entrance to a Protoss base when they are in siege mode.
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While you are not at all required to do this and they made it pretty difficult for you to do so by intentionally creating "choke points" at the entrance to any of the bases, it CAN be done and I found it quite rewarding to completely eliminate all of the Protoss structures when the only thing you really had to do was keep them at bay long enough to open the temple door. If you haven't yet done this on this map, I suggest you get in there and test your skills and see if you have what it takes to make this happen. It's loads of fun!
By default, when the temple door drops below 1000 hp or whatever that is, the Protoss will launch an all out assault if you haven't eliminated all their structures. The idea here is that no matter what sort of defense you have built up that this final assault will nearly wipe out your defenses just as you crack the last bit of "health" from the temple door. If they don't have any means of producing units though, they can't really do this final attack now can they? This takes about the same amount of time as it would to simply defend and crack open the temple door and i find it a lot more entertaining.
This is one of the few instances in this game that I can recall where you had an objective that you could take to the "next level" if you wanted to and totally dominate your opponent rather than just defeat them.