after completing the story there aren't very many gems and once you get to just B rank I'm getting put up against lvl 90 players that have way more than me so I can't even play league battles because that and my team mates that are very bot like I just wind up losing or getting one shot with 9000 health and on top of that from what I've seen you don't get very many ways to F2P grind up your characters because of the way you get shards for characters make you wait 4 hours for 1 shard