Sapphire Robe

Sapphires turn up early and in quantity, so this is usually the first robe a magic character can actually afford. Treat it as a stopgap. Make it, wear it while you are digging for better stones, and replace it the moment a rarer gem starts stacking up. The spread in defense across the whole robe family is small enough that upgrading is a convenience rather than a priority.

The body piece is only half the decision. Whichever gem you are wearing, a Wizard Hat gives you critical hits and a Magic Hat gives you a deeper mana pool. Crit rewards a fast weapon you can hold down; mana rewards a heavy one you keep running out of fuel for. Neither cares what is on your legs.

A gem robe worn with anything other than a Wizard Hat sharply raises how often Tim spawns in the caverns. That is how most players get the Magic Hat at all. He is not dangerous by himself, but the extra spawns add up when a cave is already throwing enemies at you, so take the robe off once you have what you came for.