https://www.youtube.com/watch?v=oZbK8zc3GGw

The gist of this build is a Nature Cleric and upcasting Guardian Spirits and using Thorn Whip to pull enemies in and the Telekinetic feat

Instead of using Thorn Whip.. is Eldritch Blast with Grasp of Hadar better? Probably not because of how Pact Magic affects spell slot progression; Pact Magic gives spell slots based on their own progression. It does allow you to have more than 4 spell slots at a given level, so it's not too detrimental but does slow the ability to upcast Spirit Guardians.

Instead of cleric... is Divine Soul better?

Fathomless Warlock with Ray of Frost using the tentacles and Spirit Guardians (or other sources of difficult terrain) should be able to lock things in place