I don't see any current limiting resistors in the Base traces to the transistors.
I also don't see any capacitors on the regulator input/output or decoupling capacitors on the MCU voltage pins.
for a start the transistors seem to short out your battery
Quotefor a start the transistors seem to short out your batteryHow do I hook up the NPN Transistors? I have the 9v+ flowing into the collector the -(negative) hooked to the emitter and the ATtiny84 switch hooked to the Base.
I can't wrap my mind around the NPN transistors!!! :0
Ok, so you have 20 sets of 3 led's, you say they are 3.5v and 75ma? So you would need something like 1.5amps to run it.
If you dropped it to 15-20mA per strand you could run that led circuit on a 555 timer....