Entangling Asp

Energy in the form of a spectral asp bites into your foe, bringing it to a halt. Choose a creature you can see within range. The target must succeed on a Constitution saving throw or become poisoned, and it's movement speed reduced to 0, until the start of your next turn. If the target is missing any of its hit points, it is also knocked prone. Creatures immune to poison are not affected by this spell.