1. Whack the mole DUH..
2. I mean press number key correspoding to appearance of enemies,
which are - π½, π and π.
3. Make sure to get nutrition along the way - π, π, π² before you
run out of energy. One energy point depletes for every 3 alien
kills.
4. And if you kill the baby - πΆ, then its game over for you, you
psychopath!!
GOOD LUCK :)