Each character starts with their own two Inspirations. At three points during a run an additional Inspiration from another turtle will be offered as a reward.
This are offered from the Gauntlet Mini-boss in The Sewers, the first room of The Docks, and both the regular and Gauntlet Mini-boss of The Streets.
Michelangelo Inspiration 1
Level 1
Cost: 200 
need: 3 
+5% Attack area size. +5% Attack damage.
Level 2
Cost: 450 need: 2 
+10% Attack area size. +10% Attack damage.
Level 3
Cost: 700 need: 4
+15% Attack area size. +15% Attack damage.
Michelangelo Inspiration 2
Level 1
Cost: 250 need: 3
+5% Multi-Hit chance.
Level 2
Cost: 400 need: 2
+10% Multi-Hit chance.
Level 3
Cost: 600 need: 4
+15% Multi-Hit chance.
Leonardo Inspiration 1
Level 1
Cost: 200 need: 3 
+5 Master Strike damage.
Level 2
Cost: 450 need: 2 
+10 Master Strike damage.
Level 3
Cost: 700 need: 4
+15 Master Strike damage.
Leonardo Inspiration 2
Level 1
Cost: 300 need: 3
Grants +1 Special charge.
Level 2
Cost: 600 need: 3
Grants +2 Special charge.
Raphael Inspiration 1
Level 1
Cost: 200 need: 3 
+5% Special Critical Hit chance.
Level 2
Cost: 450 need: 2 
+10% Special Critical Hit chance.
Level 3
Cost: 700 need: 4
+15% Special Critical Hit chance.
Raphael Inspiration 2
Level 1
Cost: 250 need: 3
+3% Attack Critical Hit chance. +3% Critical Damage.
Level 2
Cost: 500 need: 2
+6% Attack Critical Hit chance. +6% Critical Damage.
Level 3
Cost: 700 need: 4
+9% Attack Critical Hit chance. +9% Critical Damage.
Donatello Inspiration 1
Level 1
Cost: 200 need: 3 
Restore 1 Health upon starting an ecounter
Level 2
Cost: 450 need: 2 
Restore 2 Health upon starting an ecounter
Level 3
Cost: 700 need: 4
Restore 3 Health upon starting an ecounter
Donatello Inspiration 2
Level 1
Cost: 300 need: 3
Tool charges 20% faster.
Level 2
Cost: 600 need: 3
Tool charges 40% faster.
Casey Inspiration 1
Level 1
Cost: 200 need: 3 
Special applies Guard Break for +1s to enemies hit.
Level 2
Cost: 450 need: 2 
Special applies Guard Break for +2s to enemies hit.
Level 3
Cost: 700 need: 4
Special applies Guard Break for +3s to enemies hit.
Casey Jones' Inspiration 2
Level 1
Cost: 200 need: 3
Using your Special makes your next attack a Final Attack with +33% Crit Chance.
Level 2
Cost: 450 need: 2
Using your Special makes your next attack a Final Strike with +66% Crit Chance.
Level 3
Cost: 700 need: 4
Using your Special makes your next attack a Final Strike with +100% Crit Chance.
Metalhead Inspiration 1
Level 1
Cost: 200 need: 3 
On Boss defeat, upgrade a random enhancement and gain 25 Scrap.
Level 2
Cost: 450 need: 2 
On Boss defeat, upgrade a random enhancement and gain 50 Scrap.
Level 3
Cost: 700 need: 4
On Boss defeat, upgrade a random enhancement and gain 75 Scrap.
Metalhead Inspiration 2
Level 1
Cost: 200 need: 3
Tool applies Guard Break to enemies hit for 3 seconds.
Level 2
Cost: 450 need: 2
Tool applies Guard Break to enemies hit for 6 seconds.
Level 3
Cost: 700 need: 4
Tool applies Guard Break to enemies hit for 9 seconds.