If you still need kills after completing all of the missions, quests, ect. go into any store and raise your gun at the clerk. It will trigger a hold up and raise your wanted level. I strongly advise completing the kills before the end of the game. You can also go to the military base on the island in the southeast and create havoc to get your wanted level up as pointed out by ArrogantGenius.
"Targets" quests such as Virus Injection and Flashpoints are great for getting these kills. Just start one, kill a bunch, then, when you are about to complete it, run away. You can then come back to it later and all the enemies will have respawned.
DRedWingsDJY highlights a strategy I highly recommend if you haven't gone too far into the main story. For the gun and super power kills, he recommends getting them during the 'Emergency Situation' campaign quest. During that quest, only low-level ground aliens and gang members spawn. You can stand on rooftops and blast away without increasing your notoriety. You'll still need to work on the Singularity gun, Fire ignitions, and Deaths from above since those won't be unlocked in the campaign yet.
Plan ahead and arm yourself with the desired guns. It is very difficult to change weapons during this mission because the enemies will constantly interrupt you inside the weapon stores.
The Collectible Finder upgrade is unlocked after completing Matt Miller's "The Pledge" side quest. A must have that saves time rather than randomly searching or using a map.
When going for the collectibles, the bookmark system on the map screen can really save a lot of time by not having to switch back and forth from the map screen.
If you are having trouble completing some of the activities, quests, targets, ect. and are playing on normal or hard difficulty, just turn the difficulty down to easy. It will give you more time in certain events and has no effect on achievements since none of them are based difficulty. Credit to lionpants.
Complete All Other ChallengesEarned when completing all of the challenges.
Blazin’ Gold MedalsThe gold medal time is 15 seconds for each course, reaching a checkpoint stops the clock, and avoid fire as it reduces time by 2 seconds.
Genki’s M.O.M. Gold MedalsBe as quick as possible moving from location to location.
Insurance Fraud Gold MedalsJump high and rag doll yourself. Hitting cars will multiply your score. Saran447 says that if you fast sprint towards a car and press RT or LT just before you hit the car, it can fling you into the air. Especially useful because even if the car is stationery, it will still throw you into the air.
On-Foot Mayhem Gold MedalsThe best strategy for these activities if you are having trouble is once you reach level 26, is to unlock the Super Sprint 'Tornado' upgrade. Then instead of using the weapons or TK/Stomp powers, just super sprint around running into cars, people, everything. For the TK Mayhem, be sure to grab the giant orb as well. Thanks to Cornflopper for this tip.
Super-Powered Fight Club Gold MedalsBest done after upgrading all powers to at or near max. Most difficult activity for me. Freeze and stomp were most effective. Go after only the boss in the final round as he is the only one you have to defeat. Another way suggested by SiebeTolsma is to just sprint from enemy to enemy, and using the beatdown to quickly take them down. Perfidious Sinn says use the Shrink (Stomp) element. If you shrink any enemy, even a boss, and then melee them it kills them instantly.
Vehicular Mayhem Gold MedalsBlow things up with the given vehicle.
Platforming Rift Gold MedalsUpgrade super jump. Better to take your time rather than speeding through. Falling off will reduce the score bonus at the end of each segment.
Speed Rift Gold MedalsUse the boost as much as possible. While boosting hitting barriers increases score.
TK Rift Gold MedalsUpgrade Telekinesis throw cost and recharge. Keep your combo high to get the maximum score from each hit. Helps to have the ability to not rag doll from explosions.
10 Aliens Super-KickedClick right stick while unarmed to super-kick.
100 Death From Above KillsUnlocked late in the game by completing the "The Very Next Day" main quest. If you are having trouble getting kills, you can use freeze blast on the enemies before bombing them. Leave some Flashpoints or Virus Injections unplayed until it is unlocked. Start a Flashpointsor Virus Injection and get some kills then right before you are about to complete it, run away. The quest will cancel and you can restart it. InfernalDante34 says start the Medium difficulty Super Power Fight Club (the one with Julius). The third round is a "King of the Hill" round, and the enemies will continue to spawn (two on the map at a time). Also, it takes TWO hits with Death from Above from any height to kill them, so it is quicker to do small jumps and hit the enemies with it quickly. You MUST finish the challenge for the kills to count though, if you let the timer run out none of your kills will count.
25 Miles Super SprintedYou'll get it over time. The Unlimited Sprint upgrade is unlocked by completing Keith David's side quest "Executive Orders".
10 Superpowered BeatdownsWhile unarmed, hold down LB and use LT or RT on an enemy to perform a melee attack. Credit to fuzzyjw510.
1800 Seconds of Super Jump Air TimeYou'll get this over time.
30 Telekinetic CatchesTo unlock the Telekinesis Catch element earn all Silver Medals in the Genki's M.O.M. activity. A red beam of light shows the warden is holding something. When he throws it press RB with telekinesis while looking in his general direction. Almighty Jei says that sometimes, but not all the time, he would catch the object and throw it back, enabling the chance to catch it back. Much better than waiting for him to pick something up on his own.
30 Telekinesis KillsTelekinesis someone and throw them at a nearby wall. They must die from the impact. Easier when upgraded. Telekinesis is unlocked by completing the "Ghost in the Machine" main quest.
Throw 100 Enemies With TelekinesisDon't have to kill them. Just throw them.
10 Vehicles Super-KickedPress right stick while unarmed and standing next to a vehicle.
10 Arc Lightning HitsUse the telekinesis lightning element or buff lightning element on enemies. Don't have to kill them. The telekinesis lightning element is unlocked by completing CID's side quest "Obey (One More Time)". The buff lightning element is unlocked by completing Ben King's side quest "The Climax".
10 Enemies Mind ControlledUse the blast mind control element on enemies. Don't have to kill. The blast element mind control is unlocked by completing Matt Miller's side quest "The Prestige".
10 Fire Element IgnitionsUse the buff fire element on enemies. Must kill them. The buff element fire is unlocked by completing the "Emergency Situation" main quest.
100 Freeze ShattersUse the blast or buff freeze elements to freeze enemies and shatter them. Must kill the enemy. The buff element freeze is unlocked by completing Ben King's side quest "Ghost Writing".
10 Gravity Float KillsUse the stomp gravity float element on ten enemies and kill them while they are floating. The stomp element gravity is unlocked by completing Fun Shaundi's side quest "Something to Prove".
75 Ground Stomp StunsUse the stomp rock element on enemies. To get a ground stomp stun, just run into the middle of a group of enemies and press RB with the ground rock element. Don't have to kill them. Ground stomp is unlocked by completing the "Anomalous Readings" main quest.
10 Enemies Health StolenUse the telekinesis life stealing element on 10 enemies. Don't have to kill them. Unlocked by completing CID's side quest "Obey".
10 Shrunken Enemies SquishedUse the stomp shrink element on enemies. Then step on them ten times. The stomp element shrink is unlocked by completing Fun Shaundi's side quest "Shaundi's List".
250 Bounce Rifle KillsGet kills with it. Unlockerd during the story mission "Ghost in the Machine."
250 Dubstep Gun KillsGet kills with it. Unlocked after completing the Keith David side quest "Campaign Trail of Destruction."
150 Targets AbductedUse the Abduct-O-matic gun. Unlocked by completing the "Complete One Other Challenge' challenge.
250 Targets BlackholedGet kills with the Singularity Gun. Unlocked after completing Johnny Gat's side mission "WWGD."
100 Enemies DisintegratedUse the Disintegrator to kill. Unlocked by completing the "Back by Popular Demand" main quest.
50 Inflato-Ray KillsGet kills with it. Unlocked after completing Pierce's side mission "Fun Trumps All."
250 Mech Suit KillsYou will get most of these during the main story and Mech Mayhem activities. Replay the Mech Mayhem activity if still short.
30 Tentacle Bat BeatdownsBeat people with it. Unlocked during Kinzie's "Customizations" side quest.
Destroy 100 Alien VehiclesWill probably come naturally but Tank Mayhem is the shortest route.
Destroy 100 C.I.D.SKill the orbs that fly about and give shields. You can farm these during the last mission of the game.
Destroy 60 MurderbotsYou'll get it over time.
Destroy 30 PortalsYou'll get it over time.
Kill 1000 AliensYou'll get it over time.
Kill 30 WardensMax out your wanted level and they will appear if you still need some post-game.
20 Minutes of Alien High Notoriety TimeYou'll get it over time.
50 Aliens TauntedWalk up to and enemy and hold Left on the D-Pad. Wookiee Hairem suggested doing them at flashpoints because you can get 4-5 each time you taunt. Samphaa said that if you need taunts but have finished all the hotspots, replay the fight club in Loren Square. Get to the 2nd round and just keep jumping in one spot, when you have about 10 enemies below you, freeze them, then land and taunt them.
39 Audio Logs CollectedThey appear on the map only after completing each characters rescue mission. Unlock the Collectible Finder upgrade to find them or use this map.
http://i.imgur.com/zU8Y0kL Source: www.vgfaq.com
150,000 Feet Traveled in Alien VehiclePost-game, grab a Void (the alien jet) and fly from end to end of the city. When the jet reaches the edge of the map it will turn around and enter hover mode. Hit B to switch it back to flight mode. If you care to do this early on, xxB3averHunterx suggested that the UFO mayhem activities give you roughly 30,000 feet traveled in 3:00 if you switch to plane mode & just circle the area right from the start.
4 Miles Traveled in Mech SuitWill get this playing the main game and the Mech Mayhem. Replay Mech Mayhem if you still don't have it.
8 Text Adventures CollectedUnlock the Collectible Finder upgrade to find them or use this map.
http://i.imgur.com/lNdgZ6B Source: www.vgfaq.com
120 Minutes Spent With HomiesCall Homies or find random friendly Saints on the street and Up on the D-pad to get them to follow you. Starting a main story quest or side quest will dismiss them.
36 Zinyak Statues DestroyedDestroy Zinyak Statues found around the city. Every Planet Zin (Planet Saints) clothing store will have 2, one on the front of the store and one inside of the store in the back. Unlock the Collectible Finder upgrade to find them or use this map.
http://i.imgur.com/RwYRsri Source: www.vgfaq.com
If anyone could let me know the missions that unlock the unique weapons and upgrades would be greatly appreciated.
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