This may or may not be an improbably complete list of the standard Improbable Island inhabitant's titles, with the number of Drive Kills needed to earn that title.1)

TitleDK's
Rookie0
Contestant1
Returning Contestant2
Civilian3
Contender4
Citizen5
Private6
Lance Corporal7
Corporal8
Sergeant9
Technical Sergeant10
Master Sergeant11
First Sergeant12
Warrant Officer13
Second Lieutenant14
Lieutenant15
Captain16
Major17
Lieutenant Colonel18
Colonel19
Brigadier20
Major General21
Lieutenant General22
General23
Improbable General24
Major Badass25
Lieutenant Badass26
Badass27
Notable Badass28
Extreme Badass29
Chancellor Badass30
Prime Badass31
King/Queen Badass32
Emperor/Empress Badass33
Improbable Badass34
Royale Badass35
Royale Badass with Cheese36
Royale Badass with Special Sauce37
Lord/Lady High Badass38
Lord/Lady High Badass Supreme39
Impressive Lord High Badass Supreme40
Grand Master/Mistress Badass41
Grand Master/Mistress Badass of the Number 4242
Grand Master/Mistress Badass of Fury43
Grand Master/Mistress Badass of Rage44
Grand Master/Mistress Badass of Big Explosions45
Grand Master/Mistress Badass of Most Awesome Destruction46
Grand Master/Mistress Badass of Improbability47
Lord/Lady Elevated Badass of the Gods48
Grand Lord/Lady Elevated Badass of the Gods49
Transcendent Grand Lord/Lady Elevated Badass of the Gods50
Transcendent Almighty Emperor/Empress of Improbability with Holy Cheese and a Side of Badass Fries60
Bloody Showoff70
Bloody Ridiculous Showoff80
Ludicrous Over-Achiever90
Someone'd better buy a custom title for100

Below this line, there be lies.2)

Master Nomologer400
The Wizard of Noms400
The Watcher1,000,000
Admin1,000,0002
Mom3)1,000,0003
Full Metal50 Bastards
LionSneaky Bastards
SquatThieving Bastards
DerpThe one and only
SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1SpiderKitty Launcher with Integrated Chainsaw +1!At 385 characters,4) this was the longest title (im)possible.5) Awarded for breaking the Island in a very specific way after one's 40th DK. This title was only possible to achieve from 2016-06-13 to 2017-07-08,6) and was only held by Full Metal Lion.7)8)
1)
Your mileage may differ
2)
Or are they truths? :O
3)
Hi, Mom!
4)
longer than the chat character limit!
5)
Its evil twin, “SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1SpiderKitty Launcher with Integrated Chainsaw -1!”, is just as long
6)
though if the title was achieved in that window, it could technically be held indefinitely, as long as one avoided changing one's title
7)
Though most of the time he went by 'Like a hundred “SpiderKitty Launcher with Integrated Chainsaw +1”s! Full Metal Lion' in order to avoid the wrath of the other denizens of Banter
8)
Quote from CavemanJoe create upon seeing Full Metal Lion don this title: “How the fuck did you do that.”