The game is snowballing out of control. Reason? Keystones

With the new keystones every level you get/item it increases your damage output. For example: Fervor of battle. If you net a kill you'll get 300g, a level with stats boosts and 6 potential more damage.

Thunderlord? 10 damage per lvl+ AD or your AP scaling. With old masteries we got... +6% of damage.

Add up to that the champions that are top tiers are the ones that can abuse the key stones. Brand was nerfed because of deathfire touch. Yi is good in the jungle because of the synergy of devourer+fervor+rageblade and his passive. Kayle can proc thunder lord with 2 AA or Q and a AA and can proc furor 2 with and E auto. Lux can abuse thunderlord decree the same way. Yasuo and trynda broke bloodlust and it got all changed because of them. Panteon is a pain to lane against because of thunderlord extra damage.

Keystones are turning lol into dota.