Attack

Two main factors exist when determining the Chance to Hit:
-relationship between attacker level and defender level
-relationship between attacker ar and defender dr

The two combine into the Chance to Hit equation: Chance_tohit = 2 * Level_attacker / (Level_attacker + Level_defender) * Attack Rating_attacker / (Attack Rating_attacker + Defense_defender)

The Chance to Hit is eventually capped at 95% and bottoms out at 5%. These caps do not apply if the chance to hit formula is not used or considered.

The level component

The level component is defined as

2 * Level_attacker / (Level_attacker + Level_defender)

When the Attacker's level and the Defender's level is the same, the result of the equation is 1. It ends up having minimal effect on the total chance when attacker and defender are close in level.

The AR-DR component

The AR-DR component is defined as

Attack_attacker / (Attack_attacker + Defense_defender)

When the Attack rating of the attacker matches the Defense of the defender, the result of this component is .5 (50%).

Estimation

The main difference between the two components is that the level component is multiplied by two. As a result, the same estimation procedure can be used for both components without much modification needed.

For the level component, take the ratio between Attacker level and defender level and find a similar ratio in the table.

For the AR-DR component, take the ratio between Attack rating and Defense rating and find a similar ratio in the table.

Multiply them together and double the result.

Multiplier for Player attacking Another Player	Player amount	Another Player amount	Multiplier for Another Player attacking Player
0.98	64	1	0.02
0.97	32	1	0.03
0.94	16	1	0.06
0.92	12	1	0.08
0.91	10	1	0.09
0.89	8	1	0.11
0.88	7	1	0.13
0.86	6	1	0.14
0.83	5	1	0.17
0.8	4	1	0.2
0.78	7	2	0.22
0.75	3	1	0.25
0.73	11	4	0.27
0.71	5	2	0.29
0.69	9	4	0.31
0.67	2	1	0.33
0.65	15	8	0.35
0.64	7	4	0.36
0.62	13	8	0.38
0.6	3	2	0.4
0.58	11	8	0.42
0.56	5	4	0.44
0.53	9	8	0.47
0.52	17	16	0.48
0.51	33	32	0.49
0.5	65	64	0.5
0.5	1	1	0.5

Example:

Let's say player A is level 64 and has 3000 AR. Player B is level 66 and has 2000 defense. Find the chance of player A hitting player B.

Multiplier for Player attacking Another Player	Player amount	Another Player amount	Multiplier for Another Player attacking Player
0.6	3	2	0.4
0.51	33	32	0.49

Level ratio is 32:33 and thus, we read .49 from the table. AR ratio is 3:2 and thus we read .6 for that. Multiply them all to get .49 * .6 * 2 = 0.588 or 58%.