To defeat the Twins you want adamantine armor, greater healing potions, the Excalibur, the Demon Scythe, and some star and heart statues.
Make a sky bridge the make two or three sections each with a pressure plate and wires connecting to one star statue and one heart statue.
You’ll also want Hermes boots, Flurry boots, Spectre boots, or some Lightning boots.
For me Spazmatism was the hardest of the two but on your sky bridge with one of these pairs of boots you can outrun his flamethrower.
Retinazer’s lazers will usually hit you so the sections with heart and star statues will help a lot.
You can try to space them apart where when your mana is almost gone or your life is getting low you will trigger one of the and it will heal you.
Your main weapon should be the Demon Scythe or if out of mana a good repeater or bow after some practice it is fairly easy so… have fun gathering Souls of Sight!!!
hope this helps 🙂