Ares/Prime

Ares is the first Online Battle season rewards character. He cannot be unlocked, and can only be obtained in limited quantities by ranking high in his online seasons. Eliting him thus takes a very long time and cannot be done with Power Credits. With Ares dealing high amounts of damage and having a deadly passive, it's no wonder he's been held back for the longest time and is highly sought after in multiplayer seasons.

Strategy
Ares Prime is a character with decently high base damage and his special 2, God Smack, shocks his target for 10 seconds, thus making the whole enemy team lose their ability to block. If God Smack disables block, other opponents would also be unable to block even if the previous opponent is knocked out, or if they tag in by themselves. If God Smack itself deals the knockout block, the block disable will not be passed to the next opponent. If the opponent is knocked out from his basic attacks, and you use God Smack right away on the next character that tags in next, the special itself will miss, but the block-disable effect will be applied to that character.

Ares' SP1 has an extremely slow animation, making it easy to block and further encouraging use of his very powerful SP2.

Good with

 * Gears/teammates that increase Power generation, optimally Ra's Al Ghul's Scimitar.
 * Batgirl/Prime: Grants you one bar of starting power. Another bar closer to unleashing God Smack.
 * The Joker/The Killing Joke: Best third member for the line up above.
 * Harley Quinn/Suicide Squad: Her special 2 includes an extra trick that can immediately give him one bar of power.

Good against

 * Raven, Green Lantern/John Stewart, The Flash/Elseworld, Bane etc: Ares' special 2 is a one-hit unblockable nuke, making cards with low-health abilities-trigger ineffective against him.
 * Static/Prime: Static's passive cannot activate if he cannot block.
 * Superman/Godfall: Same as above.

Countered by

 * Doomsday/Containment, Solomon Grundy/Regime and Solomon Grundy/Prime: Their on-death revival passive is always effective against single hit high burst damage. However, seeing that they could resurrect from God Smack, it'll trigger Ares' passive and render them unable to block.
 * Harley Quinn: While not immediately apparent, Harley's special 2 runs in real time, allowing her to stall for several seconds while the block disable ticks down.
 * Mother Box: Characters equipped with it have a chance to avoid Ares' infamous special 2. If he is the starting character and geared with Ra's Al Ghul's Scimitar and/or teamed with Batgirl/Prime (this gear/teammate combination being the only one that allows him to unleash a God Smack at the start of a match and also being very popular), then the gear will also drain his power if equipped on any character on the opposing team.
 * Batman/Dawn of Justice, The Flash/Reverse Flash, Superman/Injustice 2, Riddler's Staff: All three have a chance of avoiding both God Smack and his passive, although Reverse Flash can mitigate the damage from the special, but not Ares' passive.
 * Hawkgirl/Blackest Night, Fourth World Set: Their resurrections work very similarly to Containment/Doomsday's, albeit less effectively.

Abilities
Here are Ares' abilities.

Support Cards and Gear
Here are Ares' support cards and gear.

Trivia

 * Previously, if God Smack knocks out an opponent, the block disable will be passed on the next opponent that tags in, but this functionality has been removed by the 2.6 update and now it will not affect the next opponent.
 * As of the 2.7 update, his passive has been somewhat restored; if God Smack KOs the opponent, the block disable will not transfer to the next opponent. If it does not KO, however, all opponents will be incapable of blocking for the normal 10 seconds; even if the affected character tags out, the next character will still be unable to block until it wears off.
 * Ares is the last character to have a 1-hit SP2 (without counting Harley Quinn/Arkham Knight and Harley Quinn/Suicide Squad due to the unique nature of their SP2).
 * If the opponent is able to survives his Super Move, the arrows from the animation would still be stuck into the opponent until the they either Tag out or is knocked out.