Trødwick's Shielding Sphere

You touch one creature that is Medium or smaller. Until the spell ends, the creature is surrounded by immobile, faintly shimmering shield made of pure magical force for 1d4 of the caster's turns. Nothing can physically pass through the shield. It is immune to all damage,no spells can pass through it and the area within the shield is excluded from any AoE effects. A dispel magic spell destroys the shield instantly.

If you target a non-willing creature, that creature must succeed on a Dexterity saving throw to avoid the spell.

When the spell effect would end, the caster can use an action to spend a 1st level spell slot to prolongue the duration of the spell by another 2 turns.