• If you're just starting out make sure to get a second dash and Splinter's Revive.
• After that all the upgrades are good but don't neglect the Swiftness upgrade. Being able to move out of the way helps you live a lot longer.
• Upgrade your Inspirations.
• Don't pollute your build too much. The game is weighted towards giving you the same type of Powers you already have. Powers are generally stronger the more you have of the same type, so don't be afraid to take another room reward if you aren't offered the flavor of Power you want. If you're going for a Flame and Water build, picking up an Utrom Power can hurt you more than you think. You're better off taking the scrap so you can buy another Flame or Water Power at the next Shop instead.
• Scrap is good. Being able to consistently get to the first Shop with 400 scrap to buy a Power is a big milestone.
• Once you can get there with 800 or 1200 scrap save your dice to reroll the Shop to buy multiple Powers.
• Dice are great. If you reroll the Shop all the options will be available to buy again.
• Global damage boosts are great. If a Power doesn't specifically say Attack Damage or Special Damage it applies to all damage you do. Your attack, special, tools, shuriken, Master Strike, etc., and also damage over time. So if you have an Ooze build and pick up First Strike, you'll notice that every time you dash your Ooze will deal more damage for a second. Still Waters is great since it boosts everything until you do a regular attack. Astral Dark also has some big bonuses. Have fun experimenting and seeing what you can come up with.
• None of these are hard and fast rules, the more you play the game the more you'll know when to break them.

Donatello's Math Nerd Section

Math in this game is additive not multiplicative.

This means percent increases are additive and work off of your base damage. You don't multiply the result of your +% increase by your next +% increase.

So for example, Raphael's basic attack deals 24 damage. Critical Hits do +100% damage, so when he does a crit it will do 49 damage.

*Raph gets the extra 6% crit damage from his inspiration, so it's +25 instead of 24.

24 base damage
+ 25 crit damage
= 49

After he buys some upgrades and has +50% attack, his first attack will do 36 damage but his crits will only do 61, not 74 like you might expect.

24 base damage
+ 12 upgrade damage
+ 25 crit damage
= 61

Or another way of looking at that is

24
x 256%
(100% + 50% + 106%)
= 61.44

Let's look at another example with several bonuses.

Leonardo has his attack damage upgraded to +60% and Dash Attack damage to +25%.

On this run he picked up the +30% Dash Attack Damage Mastery and just got the +50% Attack Damage Boost.

His base Dash Attack damage is 25. So now when he hits an enemy he will deal 66.25 damage

25 Base
+ 15 Upgrade
+ 6.25 Dash Attack
+ 7.5 Mastery
+ 12.5 Boost
= 66.25

Or another way of looking at that is

25
x 265%
(100% + 60% + 25%
+ 30% + 50%)
= 66.25