Here is some more details on the changes to Hit in pet battles. Source
We wanted to take a moment to discuss some of the broad accuracy changes we’re making to Pet Battles in patch 5.3. The overarching goal behind these changes is to provide transparency to reduce the amount of uncontrolled randomness, where one miss often makes or breaks a match. Once patch 5.3 is live, you’ll see “hit chance” listed for all abilities, and this value will update if the pet is affected by abilities that increase or reduce the chance to hit.
In addition, we’ve removed the base 5% chance to dodge, and reduced the chance to miss opponents of higher levels from 5% per level to 2% per level. The end result should be that your attacks that should hit, will hit, and there’s greater incentive to get out there and fight higher-level pets for greater experience rewards.
In a turn-based game, randomness can be a lot of fun if handled correctly. Without a little randomness, the outcome of a match could be predicted to a high degree of certainty before the first swing, and that’s no fun. Randomness often works best when it is opt-in, often in exchange for greater attack power, longer duration, etc. In fact, many higher-damage battle pet abilities already had a reduced chance to hit, which will now be visible.
With the removal of the base dodge chance, we were left with a large number of abilities that now had a 100% hit chance. We’ve made a handful of minor modifications to some of these abilities, giving them greater damage in exchange for a reduced chance to hit. It’s worth noting that every battle pet type (e.g. Dragonkin) have at least one ability that hits 100% of the time, allowing you to opt-out of the randomness if you prefer a less risky strategy. (Check out the full list of basic abilities that have gained additional damage in exchange for reduced accuracy below.)
Finally, we’ve left the base 5% chance to gain a critical strike (for 1.5x damage), and +/- 10% damage variance on all abilities, at least for the time being. We believe that getting a crit generally feels good, and the damage variance is often enough to make a match a bit less predetermined without swinging the match heavily in one player’s favor.
We also wanted to thank the community for the great feedback we’ve gotten so far about Pet Battles. Keep it coming!
As noted earlier, the following basic attacks have had their damage increased by 5-15% and accuracy reduced by 5-15%:
"Even when you are winning soundly, you must always give your opponent a way to retreat with honor. If you don't, then he has no reason to surrender. He will fight until the bitter end, and you will pay a larger price for victory."