My son's 'roadblock with lights' toy broke. So decided to fix it and while at it I though to myself, why not spice it up a little bit by adding a micro to it?

toy-attiny-leds.ino

#include <avr/sleep.h>

// Utility macros
#define adc_disable() (ADCSRA &= ~(1<<ADEN)) // disable ADC (before power-off)
#define adc_enable()  (ADCSRA |=  (1<<ADEN)) // re-enable ADC


const int ledPin1 = 1;
const int ledPin2 = 2;
const int ledPin3 = 3;
const int ledPin4 = 4;

const int inputPin = 0;

void enterSleep(void)
{
  pinMode(ledPin1, INPUT);
  pinMode(ledPin2, INPUT);
  pinMode(ledPin3, INPUT);
  pinMode(ledPin4, INPUT);
  
  sleep_enable();
  sleep_cpu();
}

void setup() {
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);
  
  pinMode(inputPin, INPUT_PULLUP);

  adc_disable(); // ADC uses ~320uA
  set_sleep_mode(SLEEP_MODE_PWR_DOWN);
}

void blink() {
  
  digitalWrite(ledPin1, HIGH);
  delay(200);

  
  digitalWrite(ledPin1, LOW);
  digitalWrite(ledPin2, HIGH);
  delay(200);

  digitalWrite(ledPin2, LOW);
  digitalWrite(ledPin3, HIGH);
  delay(200);

  digitalWrite(ledPin3, LOW);  
  digitalWrite(ledPin4, HIGH);
  delay(200);

  digitalWrite(ledPin4, LOW);
  delay(1000);
}

void loop() {
  
  for(int i=0 ; i< 5 ; i++) {
    blink();
  }

  enterSleep();
  // Continue after reset
}