I spent the weekend spent playing the three new Overwatch team-shooter heroes that Blizzard introduced during the annual BlizzCon convention, and they offer some interesting new wrinkles to the game.

The BlizzCon demo introduced one new map (Hollywood) and three new heroes: D.Va, a mech-style tank; Mei, a frost-wielding defense; and Genji, the robot mirror version of the game’s existing ninja, Hanzo. Unsurprisingly, he’s in the offense class.

Now in closed beta, Overwatch is due to have open stress-test weekends before the end of the year, Blizzard executives said. If you missed our rundown of every one of the 18 heroes currently in the beta, you can find all the maps, support heroes and offense here and all the defense heroes and tanks here.

 As a reminder, you can swap Overwatch heroes in mid-game by returning to the spawn point or respawning there after death.

This is the last glimpse of D.Va you're going to see before respawn.

Above: This is the last glimpse of D.Va you’re going to see before respawn.

Image Credit: Blizzard Entertainment

The Widowmaker/sniper killer: D.Va

D.Va is a professional gamer-turned-hero, and she and her mech both show a ton of personality. The mech is huge and pink; her special ability icon looks like an angry bunny. But in-game, she’s all business.

Despite her heavy form and moderate movement speed while in mech mode, she has the ability to boost/glide for short periods, which makes her a lot more maneuverable than many of the tanks.

She also has a Defense Matrix shield that she can aim where you’re looking, so unlike Rienhardt, whose shield is always solidly in front of him, you can protect yourself and anyone behind you from fire from above — including Pharah’s multiple-rocket ultimate and Widowmaker’s deadly sniper fire.

Her normal left- and right-click fire, dual fusion cannons that slow her movement speed, are fine but undramatic.

Her ultimate is fantastic: You bail out of the mech, leaving it on self-destruct mode, and just about any hostiles in line of sight when it goes off will be looking at a respawn timer. The graphic is quite large to warn the opposing team, but this is fast: If you’re not already near cover (or can create your own), you’re dead.

If you take enough damage as D.Va, your mech goes down and you’re in super-squishy humanoid mode. Don’t give D.Va’s human form short shrift: While a shot or three can take her down, that little pistol of hers can pack a punch. I killed more people with D.Va’s human fire than I did as the mech — at least, until I exploded on people.

Once you’ve done enough damage as a human, or if you’re killed, you can resummon the mech.

With the speed boost and shield, you can fly directly at Widowmaker without worry, so D.Va is a direct counter to one of the more-popular (and more deadly) heroes in the game.

Mei's ice wall is an amazing tool.

Above: Mei’s ice wall is an amazing tool.

Image Credit: Blizzard Entertainment

The frost flinger: Mei

Mei rapidly made herself my favorite character, not because this defense player’s attacks hit brutally, but because of the way she can change the game.

Her abilities include a freeze ray (a nice counter for Tracer or other high-mobility heroes), which gradually slows and then stops anything it targets. A right-click throws a volley of frost shards.

One ability, Cryo-Freeze, turned out to be golden in this inexperienced crowd. It looks like a World of Warcraft mage’s ice block: It surrounds Mei in an indestructible ice shield for a few seconds, just long enough for short-attention-span offense to move to another target and then get nailed by a freeze ray from behind.

Mei moves at average speed for defense.

She offers one additional amazing ability: She can raise a wall of ice that completely blocks roughly two-thirds of a city street.

Mei’s ice wall can create a choke point in an area where none exists for a few seconds for heroes that can’t vault over it; it can block enemy fire, including ultimates. It can also launch friendly players into the air, allowing for some really interesting, game-changing mechanics.

We had a ton of fun finding new uses for Mei’s ice walls. Want to blow everyone up? Create a choke point with one and park an exploding D.Va mech behind it. The graphics of the exploding mech are invisible, the opposing team comes around the corner and BLAM. (We hit a five-kill with that one.)

Or park a Bastion in turret form where none belongs, on a high point where he can pick off the opposing team below, by using a Mei ice wall to lift him up next to a balcony he can run onto before stopping and converting into turret mode.

Mei’s ultimate ability is a device she tosses into a targeted circle that causes an ice storm, creating area of effect damage (quite powerful in the demo) and slowing everyone inside.

I can’t wait for her to show up on the beta.

Watch out for that sword; Genji is a killer melee character.

Above: Watch out for that sword; Genji is a killer melee character.

Image Credit: Blizzard Entertainment

The anti-Hanzo: Genji

Genji is the ninja Hanzo’s betrayed brother, trapped in a robot body and seriously pissed off. He is the melee version of his archer brother, with a sword that can carve through the opposing team.

Like Mei with her ice wall and D.Va with her defense matrix, he offers a hard counter to the powerful sniper classes in the game: Deflection, which sends any ranged projectile aimed his way ricocheting toward his target.

He can use a ranged attack himself in the form of Shuriken, either fired individually rat-a-tat style with a left click or tossed three at a time in a fan with a right-click.

Genji’s Swift Strike made me giggle: He zips through players in front of him, hitting them all and making them bleed for damage over time.

This turned out to be especially effective at choke points, but it takes some skill to use: If you’re not careful, you can end up zipping behind enemy lines and get gunned down by both front-liners turning to hit you and supporting characters bringing up the rear.

If you’re lucky enough to kill a low-health target with Swift Strike, its cooldown resets immediately.

His ultimate ability is Dragon Blade, with a graphic similar to his brother’s arrow-based Dragonstrike, but a bit more powerful if you use it well. Trigger it and suddenly everyone you hit with a melee blow for a short time dies. That got me out of trouble more than once when I overshot the enemy’s front line at a chokepoint.

Genji takes more skill than many in the game to operate, due to his heavy reliance on melee to dish serious damage.

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