Consider

The /consider command (or in most cases, right clicking) gives basic information about the relative experience level and faction standing of an NPC. It's a very important habit for newer players to /consider every NPC they engage in combat, especially early on when monsters vary considerably in difficulty and are mixed in placement.

Consider color scales by level

Character Levels 1 - 6

-4 and below GREEN - looks like a reasonably safe opponent
-1 to -3 BLUE - looks like you would have the upper hand
0 WHITE - looks like an even fight
+1 and +2 YELLOW - looks like quite a gamble
+3 and up RED - what would you like your tombstone to say?

Character Levels 7 - 8

-4 and below GREEN - looks like a reasonably safe opponent.
-1 to -3 BLUE - looks kind of risky, but you might win.
0, WHITE - looks kind of risky..you might win.
+1 and +2 YELLOW - looks like quite a gamble.
+3 and up RED - what would you like your tombstone to say?

Character Levels 9 - 12

-6 and below GREEN - looks like a reasonably safe opponent.
-4 and -5 GREEN - looks like you would have the upper hand.
-1 to -3 BLUE - looks kind of risky, but you might win.
0, WHITE - looks kind of risky..you might win.
+1 and +2 YELLOW - looks like quite a gamble.
+3 and up RED - what would you like your tombstone to say?

Character Levels 13 - 14

-7 and below GREEN - looks like a reasonably safe opponent.
-6 GREEN - looks like you would have the upper hand.
-4 and -5 BLUE - looks like you would have the upper hand.
-1 to -3 BLUE - looks kind of risky, but you might win.
0, WHITE - looks kind of risky..you might win.
+1 and +2 YELLOW - looks like quite a gamble.
+3 and up RED - what would you like your tombstone to say?

Character Levels 15 - 24

-8 or less, GREEN - looks like a reasonably safe opponent.
-6 and -7, GREEN - You would probably win this fight..it's not certain though.
-3 to -5, BLUE - looks quite risky, but might be worth a try.
-1 and -2 - BLUE - looks kind of dangerous.
0, WHITE - appears to be quite formidable.
+1 and +2, YELLOW - looks like quite a gamble.
+3 or more, RED - what would you like your tombstone to say?

Character Levels 25 - 32

-11 or more, GREEN- You could probably win this fight.
-10, GREEN - This creature could pose problems, you would probably defeat it.
-8 and -9, GREEN - You would probably win this fight..it's not certain though.
-1 to -7, BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?

Character Levels 33 - 40

-11 or more, GREEN - you could probably win this fight.
-11, GREEN - You would probably win this fight..it's not certain though.
-1 to -10, BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?

Character levels 41 - 44?

-12 or more, GREEN - you could probably win this fight.
-1 to -11, BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?

Character levels 45 - 48

-13 or more, GREEN - you could probably win this fight.
-1 to -12, BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?

Character Level 49 - 50

-14 or more, GREEN - you could probably win this fight.
-1 to -13,BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?

Character Level 60

-21 or more, LIGHT GREEN - you could probably win this fight.
-16 to -20, DARK GREEN - you would probably win this fight..it's not certain though.
-1 to -15, BLUE - appears to be quite formidable.
0, WHITE - looks like quite a gamble.
+1 and +2, YELLOW - looks like it would wipe the floor with you!
+3 or more, RED - what would you like your tombstone to say?