Wall of Fish

You create a wall of fish on the ground at a point you can see within range. You can make the wall up to 30 feet long, 10 feet high, and 1 foot thick, or you can make a ringed wall up to 20 feet in diameter, 20 feet high, and 1 foot thick. The fish fall to the ground in a heap when the spell ends. The wall’s space is very difficult, slippery terrain, impending attacking players twice as much as usual difficult terrain.

Any ranged weapon attack that enters the wall’s space has disadvantage on the attack roll, and fire damage is halved if the fire effect passes through the wall to reach its target, also creating 2d20 edible cooked fish which fall to the ground. Spells that deal cold damage that pass through the wall cause the area of the wall they pass through to freeze 2d20 fish (at least a 5-foot-square section of fish is frozen, causing the frozen fish to fall to the ground). Each 5-foot-square frozen section has AC 5 and 25 hit points and regenerates 5 hit points of fish every round. Reducing a frozen section to 0 hit points leaves a gap in the wall. When a section is dismantled, the wall's fish fill it with 5 hit points of fish each round until it restores its 25 hit point solid fish wall.

This can be used for defense or for generating 12d20 fish which fall to the ground at the duration of the spell.