To Install: Rename the "data.jet" file in the Assets folder to anything else, then move the enclosed "data.jet" file to the assets folder.
To Uninstall: Delete the modified "data.jet" file in the assets folder, then rename the original file to "data.jet

For the people who miss hardcore mode from the flash version. Makes the rounds harder; more bloons, more camos, more regens, more rushes.

Full Changelog:

RoundGenerator.xml

(Author's Note: I don't know how these values are applied exactly by the game.)

Rounds Calculator
Rounds Base Value 2>4
Rounds Increase 1>2
Rounds Cap 25>35
Round Budget Base Value 10>20
Round Budget Base Multiplier 5>10
Round Budget Increment 10>20
Round Budget Base Growth 7>14
Themes
Standard
MOAB Cluster Chance 0>0.6
BFB Cluster Chance 0>0.6
Yellow RBE 4>3
Pink RBE 5>4
Black RBE 11>9
White RBE 11>9
Zebra RBE 23>20
Lead RBE 23>20
Rainbow RBE 47>40
Ceramic RBE 104>88
MOAB RBE 616>524
BFB RBE 1848>1571
ZOMG RBE 3164>2689
DDT RBE 3165>2690
MOAB Cluster RBE 3166>2691
BFB Cluster RBE 3167>2692
Ultra-Close Spacing RBE Factor 1.5>1.3
Super-Close Spacing RBE Factor 1.2>1
Close Spacing RBE Factor 1.05>0.85
Normal Spacing RBE Factor 1>0.8
Loose Spacing RBE Factor 0.8>0.6
Ultra-Close Spacing Probability 0.03>0.2
Super-Close Spacing Probability 0.13>0.55
Close Spacing Probability 0.34>0.95
Normal Spacing Probability 0.86>1
Camo Cost 2.5>1.5
Regen Cost 1.8>1.2
Early Cost 1.2>1.1
Delay Cost 0.7>0.5
Camo Probability 0.05>0.15
Regen Probability 0.15>0.25
Difficulty Required Before Camo 12>10
Difficulty Required Before Regen 8>6
Minimum Rounds Before Camo Bloons 6>4
Minimum Rounds Before Regen Bloons 3>2
Default Minimum Rounds Before MOAB-Class Bloons 20>18
Rounds 1-9 Cash-Per-Pop 1.1>0.9
Rounds 10-13 Cash-Per-Pop 1>0.95
Camo Craziness
Camo Cost 1.5>0.9
Camo Probability 0.75>0.95
Regrow Rush Of Death
Regrow Cost 1.2>1
Fast And Furious
Black Chance 0.2>0.1
White Chance 0.2>0.4
Zebra Chance 0.2>0.1
Rainbow Chance 0.2>0.6
Hard And Heavy
Yellow Chance 0.2>0.1
Pink Chance 0.2>0.1
White Chance 0.7>0.6
Rainbow Chance 0.25>0.5
Cash Starve
Rounds 1-9 Cash-Per-Pop 0.9>0.5
Rounds 10-13 Cash-Per-Pop 0.95>0.55
Camo Regrow Pain
Camo Probability 0.7>0.8
Cluster Chaos
Ultra-Close Spacing Probability 0.2>0.4
Super-Close Spacing Probability 0.55>0.75
Close Spacing Probability 0.95>1
Normal Spacing Probability 1>0.5
Round Ramp
Pink RBE 4>3
Black RBE 9>6
White RBE 9>6
Zebra RBE 20>12
Lead RBE 20>12
Rainbow RBE 40>24
Ceramic RBE 88>48
MOAB RBE 524>284
BFB RBE 1571>852
ZOMG RBE 2689>1458
DDT RBE 2690>1459
MOAB Cluster RBE 2691>1460
BFB Cluster RBE 2692>1461