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Super Minions

After a few sandbox games, it appears that super minions are super strong. No idea if it is really about super minions or just defensive behaviour.
Everytime a team loses his first inhib, they stay in base as five and fight the open lane forever, while losing the rest of the map. Sometimes they cannot even fight two open lanes and lose nexus turrets to minions only.

Just have a couple of games, so it might be a coincidence. Otherwise this might need some sort of fix soon.
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I definitely did experience the same thing - in more than 20 Sandbox games (basically in all that I watched).

The team that loses its inhib first is 100% guaranteed to lose the game. That's why the only viable option at the moment is to say "group at 15 minutes". There is literally no advantage to try and group later, as the team that groups first will always get a strong push in one lane and will get the inhib, thus ending the game.

As such, I don't think Splitpush champs are any good at all (I'm not actually sure that AoE, Teamfight, split push, poke etc. has any meaning on the outcome though). If these stats do actually contribute, then I'd assume that champs that have AoE and Teamfight abilities are supreme and should be the way to go.