If its in trick room, Swarm powers up X-scissor and Megahorn. In case you get caught out of trick room, make it have a Custap Berry and Swarm. If it is meant to be a defensive Pokemon, give it shell armor to prevent critical hits. Here, ill give you some movesets just to "inspire".
[email protected] berry. Swarm
Megahorn: There is that power.
Iron Head: For ice, rock, fighting, poison, flying, and ghost.
Reversal: Works well on types like steel when hp is low.
Endure: You just never know when you are gonna need it.
[email protected] Shell Armor.
Iron Defence or Double Team: Both are good defencive moves.
Swords Dance: When you are maximum defense/evasion.
X-Scissor: Nice, Reliable Attack.
Iron Head: Also good. Shuckle may flinch!
Overall, I recommend Shell Armor, which is great for defensive Pokemon. I hope this helps! -Jellohamster