Saints Row 4 has a large selection of activities, targets, minigames, sidequests, and other diversions. Some of them are more challenging than others. In this guide I plan to cover strategies for all of the targets, which are indicated by red diamonds on your map.
Saints Row 4 Targets Guide: Virus Collection
"Virus Collection" is a fancy name for the "Chop Shop" activity in previous versions of Saints Row. The objective is either to go to a particular location and steal a vehicle under heavy guard, or to go to a region and find a particular type of car. Once you've found the car in question, you've got to take it to a drop off location.
There's not much to say strategy-wise here. Most of the time with the "guarded" cars you can just hop in the vehicle and take off without much of an issue.
Upgrades: Damage resistance and/or health can help some for getting past the guards. The Nitrous Everywhere upgrade can help you deal with some of the slower vehicles like the chrome-plated armored car.
Co-Op Rating: 1 out of 5. You can't both be on the same Virus Collection mission, so your partner can't help you track the car. They could ride shotgun for you, but honestly it shouldn't be necessary. If you have time when you're not playing co-op, these are a good mission to focus on.
Saints Row 4 Targets Guide: Security Deletion
"Security Deletion" is the new name for the Assassination missions of Saints Row 3. However, unlike in Saints Row 3, there aren't any fancy unlock conditions for these targets. You just have to go to the marked area and wipe them out. There are occasionally decoys, however.
Upgrades: It pays to bring a pretty upgraded weapon, since sometimes the targets have high health. The specific weapon isn't that important, though. Since there's combat, damage resistance and health can both be helpful.
Co-Op Rating: 3 out of 5. You can split up and take out the decoys individually, although you'll both have to be on the mission. The only way for both of you to be on the mission is to pick it from the side quests menu individually.
Saints Row 4 Targets Guide: Flashpoint
"Flashpoints" are just a group of aliens surrounding a small obelisk-style object. Kill all the aliens, and the flashpoint is yours.
While you can rush in headlong, guns blazing, you can also use cover or the corners of buildings to reduce the number of targets that can hit you at once. Using a tactic like this and some careful headshots, you should be able to clear Flashpoints no problem even in the early game.
Upgrades: Again, damage resistance and health, since you're going to be in combat. Just a few shots from an upgraded area-of-effect weapon like the Abduction Gun, the Dubstep Gun with the Explosive Wubs upgrade, the RPG, or even an upgraded Bounce Rifle will clear a flashpoint quickly.
Co-Op Rating: 2 out of 5. It's nice to have help for these, but honestly they're over so quickly that it usually isn't worth it to try and coordinate an assault.
Saints Row 4 Targets Guide: Virus Injection
"Virus Injections" are the Saints Row 4 equivalent of survival challenges in Saints Row 3. At least this time you don't have to wait for your homies to call you on the phone - they're unlocked on the map from the start.
Virus Injection missions are actually pretty good for getting your Challenges completed. Since the enemies tend to just stand around in tight circles around the activity start point, you can get a large amount of enemies with a single shot of an area-of-effect weapon like the Abduction Gun. Power Challenges are likewise easy to farm during these missions.
Upgrades: Health and damage reduction related upgrades, yet again. Generally you're not going to see many of the higher-end aliens during these, so focus on bullet damage reduction.
Co-Op Rating: 3 out of 5. These can take a bit longer than a Flashpoint does, but still you shouldn't have much of a problem soloing these.
Saints Row 4 Targets Guide: Towers
Towers are brand new for Saints Row 4. The only objective here is to climb your way to the top of the tower. Along the way, you can usually find a large quantity of Data Clusters for upgrading your powers.
Of course, you could always cheese this and just use a Void or an XOR to bypass all the jumping. However, there are a few drawbacks. One is that you still need to get the clusters, and some of these are going to require you to get off your VTOL. Also, these challenges just aren't that hard, what with all the checkpoints and the relatively low difficulty level of the platforming.
Upgrades: Jump upgrades, clearly. The Wall Running upgrade is nice as well, as it makes getting some of the Clusters stuck to the wall a bit easier.
Co-Op Rating: 1 out of 5. There's not really that much of a benefit to doing this together, except for perhaps the fact that you can get credit for your partner's cluster pickups and vice versa.
Saints Row 4 Targets Guide: Beacons
Beacons are like Flashpoints on steroids. There's a set of satellite locations that you have to clear to bring the massive shield down, and then you've got to assault the central spire.
Around the area are sentry gun emplacements that you need to take down in order to avoid taking massive damage. You can also push these off the elevated platforms if you wish.
Some of the Beacons have floating platforms that more or less require you to get in a Void or XOR to get to them.
The central spire tends to be heavily guarded, but in many cases you can just rush the objective and break it before they can kill you. If you're having issues, remember that you can pause and summon a tank or Void on demand!
Upgrades: Damage resistance, health upgrades - you know the drill. Some powerful weapons are a smart choice as well.
Co-Op Rating: 4 out of 5. There are several independent targets around the outside, and then there are generally enough troops defending the center that having two people can be a benefit.