Tier
Upgrade
Prerequisites
City Cash cost
Bloonstone cost
Time (minutes)
XP for researching
1
Extra Range
—
200
—
10
25
2
Frag Bombs
City Level 4
1,200
—
90
60
3
Cluster Bombs
City Level 12
7,500
20
2,160
350
4
Bloon Impact
City Level 20, High Explosives Workshop built
40,000
50
1,440
800
1
Bigger Bombs
—
300
—
15
30
2
Missile Launcher
City Level 6
1,200
—
90
50
3
MOAB Mauler
City Level 12, Anti MOAB Research Lab built
7,500
20
2,160
225
4
MOAB Assassin
City Level 20, Advanced Rocket Lab built
30,000
50
2,880
800
Tier
Upgrade
Prerequisites
City Cash cost
Bloonstone cost
Time (minutes)
XP for researching
1
Increased Accuracy
—
250
—
10
25
2
Bigger Blast
City Level 4
1,000
—
120
70
3
Bloon Buster
City Level 10
6,000
20
1,440
250
4
The Big One
City Level 20, Super-Bomb Research Centre built
22,500
50
4,320
1,100
1
Rapid Reload
—
300
—
15
30
2
Burny Stuff
City Level 8
1,800
—
120
50
3
Signal Flare
City Level 12
7,500
20
1,440
90
4
Artillery Battery
City Level 20, Heavy Artillery Factory built
40,000
50
2,880
900
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