vs. Protoss

The Roach is a natural counter to Protoss tier one Gateway units (Stalkers/Zealots/Sentries) and a Protoss player attempting a 4-Gate Rush against a 7-Roach Opening is in for a surprise. Your early Roaches will be able to fend off the 4-Gate attack and your counter-attack should have devastating consequences for your Protoss opponent. 

vs. Zerg

The 7-Roach Opening is strongest against Zerg players opening with the common Zergling/Baneling build or fast expanding. The Roaches high HP and armor make them great tanks against Zergling/Baneling damage, allowing you to defend against a potential rush or punishing your Zerg opponent for fast expanding with a devastating Roach/Zergling attack. 

vs. Protoss

Your initial Drone scout should provide you with as much information as possible on the type of build your Protoss opponent is going. Effectively, stealing your opponent’s gas with your scouting Drone can help slow down your opponent’s ability to tech and reduce the number of Stalkers/Sentries they will have to defend against your Roach attack.

Roach/Zergling is the right answer against any early composition your Protoss opponent will have for their army. You will want Zerglings in your army to surround Stalkers, while your Roaches focus down Zealots. During your attack, you will want to break the Protoss wall-in by utilizing your Roaches’ range and then stream into the Protoss base with your Zerglings.

vs. Zerg

Only the basic Drone/Overlord scouting is necessary up until you have your first set of Roaches out. You will gain most of your scouting information when you push out with your first 4 Zerglings and once again when you attack with your 7+ Roach/Zergling army.

You will want to have as many Roaches in your army as possible against any composition of tier one units your Zerg opponent can muster. You will supplement your Roaches with Zerglings based on how many minerals you can expend. If you do not go for an all-in approach, you will need to prepare for a transition into the appropriate counter as your opponent reaches Lair.

Overlord Scouting
Placing your Overlords over key areas on the map will help you gain valuable information on your enemy’s movements and their plans of expanding or attacking. 

Roach Wall-In (ZvZ)
The Roach wall-in is an important aspect of the ZvZ matchup. Failure to have a true wall-in can result in a stream of Zerglings entering your base and wrecking havoc on your economy. Remember to line up your Roaches along your ramp and use Hold Position (H) to prevent your Roaches from being lured away from the ramp.

Transitions
Roaches begin to lose their great tier one value as the game begins to move into the mid-game. It will be vital to make a decision on whether you want to do an all-in attack with your initial Roaches, supplemented by reinforcing units, or to use your Roach attack to setup your expansion and transition into the mid-game. 

The 7-Roach Opening is designed to counter aggressive players that are expecting a Zerg player to fast expand. Roaches are one of the strongest tier one units and supplemented with Zerglings, they can take down any other tier one unit composition of equal size. Use this early Roach advantage to set the table for the remainder of the match as you decide on how you want to play it. All-in or expand?