You can download various Clash of Clans Private Severs or MOD APKs from here. Currently, only two private servers are here: Atrasis and Null’s Clash, both are working and support real-time battles. Also, both these servers provide regular updates. You can download for Android with these buttons:

Null’s Clash (310 MB)

Get Null’s Clash v17.18.11 for Android with TH 17, Multi-Gear Tower, Troop Launcher and Alchemist

Atrasis COC (457 MB)

Get Atrasis COC for Android v17.18.11 with TH17, Multi-Gear Tower, The Troop Launcher, The Alchemist, New Hero Equipment: The Metal Pants for the Minion Prince. If you’d wish to download Atrasis for iOS or the ultimate version where you can find custom Hero and Mods, please visit this page!