Conjuration Spells

[JesterOI]

I've noticed that entangle does work every round for how long it's supposed to last.
But have also noticed that when the spell is first cast it takes 1 or 2 rounds to force a save roll and therefore take effect.
Then once the spell has been in place for a couple round I can run right through it without needing to roll a save.

I was wondering if this is the way all of the conjuration type spell like entangle are going to work? Shouldn't they take effect the first round they are cast and force a save roll as soon as someone tries to pas through their area of effect?

Other than that lack of affecting targets on the first round and on enter, I think that the way I have seen entangle work is the way all lingering area spells like it should work. Good work!