EVENT DETECTION CONDITIONAL BRANCH

I apologize, I've been asking for help in the wrong thread. This is a different question though. Basically, what I want to do is have a conditional branch that changes the character to dead characters by detecting its distance from the character, so basically the evens in the middle and it needs to detect all around it, and then it should change into a dead person. Would be much appreciated and I will give you much love. :P

How do I make that last even call
# X and Y's
# ----------------------------------------------
$game_player.x
$game_player.y

$game_map.events.x
$game_map.events.y
# n = Event ID


# Check Terrain Tag
# ----------------------------------------------
$game_map.terrain_tag(x, y)
$game_player.terrain_tag
$game_map.events.terrain_tag

# Check Region ID
# ----------------------------------------------
$game_map.region_id(x, y)
$game_player.region_id == n
$game_map.events.region_id == n

# Check Map Name and Map ID
# ----------------------------------------------
$game_map.name
$game_map.map_id

# Check if Event is Near Player
# ----------------------------------------------
$game_map.events.near_the_player?

# True/False. Distance for detection is 20 squares.
# n = Event ID