The way to avoid fighting in the abandoned tower in Baldur's Gate 3 is to take the elevator to the basement, knock down the one with the halberd first, and then deal with the remaining four slowly. The damage of this is very high.
After the player uses the Flower of Light to start the elevator and go to the basement, there will be many structures and then use the halberd to attack.
It can get a certain amount of lightning damage, and the four crossbowmen around it will collide, making it easy to hit the first floor.
First, start the action to knock down the one holding the halberd, and then deal with the remaining four slowly.
If you bring the Whispering Flower, you will gain the ability to construct a new body. After victory, you will be able to obtain a halberd and a ring.
After putting on the captured ring, go to the elevator on the top floor to find a hidden button to go to the laboratory.