I am voting OU. In relation to the offensive characteristic: If a pokemon if capable of sweeping through an entire team with little or no effort. In my matches I have found that latias is easy to counter and has a hard time sweeping through teams. The abundancy of scizor, tyranitar and common steel types such as metagross (not to mention special sponges such as snorlax and blissey), make it extremely hard for latias to sweep through the majority of teams.
Defensive Characteristic: Latias cannot wall / stall out a significant portion of the metagame. Latias can set up dual screens and recover, but it cannot stop common pokemon from setting up against it, such as SD lucario, SD scizor, nasty plot togekiss, etc. Also, with the abundancy of pokemon that can pursuit it, it will not stay around for long.
It can pass wishes decently, but Vaporeon and Blissey do that better due to not having a horrible pursuit weakness.
Looks like Latias is officially OU, with 17 votes.
Overall, Latias seems OU.
In my experience, Latias fails the offensive characteristic.
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