I was actually thinking of that idea. Some enemies can be hurt with a certain weapon, while others can't. A spear and a shield might not be inside the game for a few reasons:
1. A spear acts similar to a dagger, just longer. It's the same animation, therefore I see it as something not needed. And although creating a spear that acts slower than a dagger, the spear would probably be less used unless there's a certain enemy.
2. I was thinking of a shield to be added to the game. However, the sword already exists and I think a sword is more than enough to destroy the arrows. And I'd encourage the player to try to move to dodge the arrows while fighting the enemies. You know, making the game much difficult.
I'd thank you for your feedback.