Almost everyone knows this tip but I will tell you anyway.
All you need is a gravitation potion [ Water, deathweed, fire blossem, blinkroot, and a feather] and a clear area going up and down. [ make sure any floating islands are not above you] Now once you have spawned The Twins fly upwards. Now because of the fact that the green eye is way faster then the red eye, when you go upwards, The red eye will get lost and it counts as the red eye being dead. So that means you only have to do 24,000 damage instead of 48,00!
Thanks for reading,