If you're using the default first-person battle system where the heroes are not visible, then whenever a skill targets a hero, it'll play the sound effects of the animation but not show the animation. This script makes those animations play in the center of the screen.
First create a completely blank, transparent image in the Battlers folder named Blank.png. This will be the graphic used by players. Make it as small as you can (1 pixel by 1 pixel would be ideal). If you make it larger then the animations will be slightly off-center.
Then add this script to your game, below the default scripts but above Main.
This script is written assuming your window size is the default of 544 x 416 pixels. If you've changed the window size, then change the numbers in the script accordingly.