Skulltula

Damage

How many points of health each attack takes off Skulltula. 0 means the attack does no damage, though it may still stun or knock it back.

Attack	Damage
Deku Nut	0
Deku Stick	2
Fairy Slingshot	1
Bombs	2
Boomerang	0
Fairy Bow	2
Megaton Hammer	2
Hookshot	2
Kokiri Sword	1
Master Sword	2
Giant's Knife	4
Fire Arrow	4
Ice Arrow	4
Light Arrow	4
Din's Fire	4
Mirror Shield	0
Kokiri Sword (spin attack)	1
Giant's Knife (spin attack)	2
Master Sword (spin attack)	4
Kokiri Sword (jump attack)	2
Giant's Knife (jump attack)	4
Master Sword (jump attack)	8
Megaton Hammer (jump attack)	0

Hits to defeat it with each weapon: damage calculator

Damage to Link

Health Link loses when an attack of Skulltula hits him, one line per attack strength, 16 points to a heart. Once a Great Fairy strengthens Link's defensive power, the damage is halved, rounded up.

Drops

When Skulltula is defeated, the game picks one of 16 slots at random, so each slot is a 1 in 16 chance. Some slots hold nothing.

Item	Count	Chance
Recovery Heart	1	4 in 16
Recovery Heart	3	2 in 16
Deku Seeds	1	2 in 16
What Link needs most	1	1 in 16
Nothing		7 in 16

What Link needs most is checked in this order: a fairy at one heart or less, three recovery hearts at three hearts or less, one at five hearts or less, a large magic jar when the magic meter is empty, a small one when it is half empty, Deku Seeds or arrows when Link has fewer than 6, bombs when he has fewer than 6, and a red Rupee when he has fewer than 11 Rupees. If he has enough of everything, nothing drops.

Young Link gets Deku Seeds where adult Link gets arrows, and the other way round, and an adult's Deku Stick turns into a green Rupee. Bombs, arrows, seeds, and magic only drop once Link has the bomb bag, the bow, the slingshot, or magic, and a recovery heart at full health turns into a green Rupee.