After multiple attempts at playing matches tonight and doing testing on customs, it appears that Viktor may very likely be the cause of the multiple reports of game disconnects where the game suddenly stops existing.( (http://boards.pbe.leagueoflegends.com/en/c/bugs/mm0JtO96-can-not-re-connect-after-disconnecting-from-games) (http://boards.pbe.leagueoflegends.com/en/c/bugs/n8yVlqUs-games-crashing-at-145-or-under) (http://boards.pbe.leagueoflegends.com/en/c/bugs/peZjEtci-dc-but-cant-go-back-in-game) ). Although I cannot confirm it, I do know that custom games without Viktor have been working fine for me, and normal games without Viktor have not crashed for me so far.
1. Have someone on either team in any game mode select Viktor.
2. Load into the game.
3. Wait 1-2 minutes. The game seems to crash only if Viktor is in use.