Right...
Well, as someone who actually has played a bunch of it.1. Lategame carries own. Antimage, Spectre, etc.
2. Gankers dominate. Guys like Spirit Breaker just own because of how many fights there are constantly.
3. Snowball heroes don't do very well. Meepo for example who relies on being higher level than everyone else is pretty trash. Bounty Hunter is another example of someone you'll never want.
4. Long CD heroes are never picked ever. The game will probably be over before you even use black hole twice. I've literally never seen Enigma or Tide. You'll constantly be in fights where your ult is not up.
5. Invis isn't invincible any more. You can buy detection any time you want. That being said, Riki's level 25 talent where his ult becomes a giant radius is super scary in this. Again, because of how much fighting there is. Also invis guys like Clinkz are super strong because they melt towers before you even know they're there.
6. Backdoor heroes are ultra powerful in general. Prophet, Terrorblyat, Antimagus, etc. But at the same time, TP cooldown is really short, so it's not particularly hard to defend against it.
7. Jungling is... difficult to pull off. You get so much less exp and gold because you're not fighting like the lanewars that go on. So it seems you'll always be underlevelled. Hell, roaming seems to pay off more than jungling.
8. Supports are fun to play. Simply because you actually have money and levels. So you can get all the cool shit and still fight like the best of them. I frequently see Rubick slaughtering carries in this.
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Honestly it doesn't feel very different from normal Dota. Except it's just faster and more fighty. It snowballs more because towers die really fast, but at the same time carries can get six slotted really fast too. The "being able to buy consumables anytime" isn't that big of a deal either. You can do it too after all, and it's not like they're free. A dumbass who has to buy 6 health pots to survive his lane is ruining his own life. It's just convenient and more arcadey. Which is probably why everyone just fights all the time. And that's fun.
In my dozen or so games, it's never really felt particularly imbalanced in either direction. We've won and lost to cheese teams as much as normal teams. So yeah, there's no real need to analyze it too much. It's just arcade mode. Hell, the pros like it too. SingSing et al are all playing it. It's just more fun when the games are only 20 minutes long and filled with nonstop fighting. And even if you're losing, meh. At least you're not stuck in that game for 50 minutes.
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I'm also not going to pretend I'm good at this game any more. It's impossible for people who've been out of it for months or years to come back to Dota as they change everything so dramatically. It's not fun to have to basically relearn the game. So I like this mode. It's chill, casual, and there's lots of fighting.