Shields are an excellent way to increase one's defense in combat. The holy Paladins of Zakarum are even said to use them as weapons. Wielding a shield increases your character's defensive rating. Additionally, some shields can completely block an attack. Only Barbarians may wield both a shield and a two-handed weapon.

You can only equip one shield at once.

Barbarians cannot dual-wield shields.

Shields cannot be used to attack monsters, they will do no damage.

Shields list Smite Damage for the Paladin which is a Paladin Combat Skill.

What do Shields Block?
Any melee attack and any ranged attack with physical damage or delivered physically, like Exploding Arrow.

How does Blocking work?
Blocking always works against physical attacks. 75% Blocking will indeed stop 75% of attacks from hitting, regardless of whether you are attacking, or standing, or whatnot. Note: that if a player is moving, the block percentage is reduced to 1/3rd of its original value. Think of it as "resist physical". The block animation will only play if you are not doing anything else. For more information go here.

Is there a Cap on the % Chance to Block?
Yes, 75% is max.

Is % Chance to Block Class Specific?
Yes, different classes may see different numbers.

	Min/Max Defense	Level Requirement	Min Strength	% Block	Durability	Sockets	Paladin Smite Damage	Type	Quality Level
Defender	41-49	22	38	[10] Pal: 40% Ama/Asn/Bar: 35% Dru/Nec/Sor: 30%	68	1	8 to 12	Light	34
Round Shield	47-55	25	53	[12] Pal: 42% Ama/Asn/Bar: 37% Dru/Nec/Sor: 32%	64	2	7 to 14	Light	37
Scutum	53-61	25	71	[14] Pal: 44% Ama/Asn/Bar: 39% Dru/Nec/Sor: 34%	62	3	11 to 15	Medium	42
Barbed Shield	58-78	25	65	[17] Pal: 47% Ama/Asn/Bar: 42% Dru/Nec/Sor: 37%	55	2	18 to 35	Light	42
Dragon Shield	59-67	25	91	[18] Pal: 48% Ama/Asn/Bar: 43% Dru/Nec/Sor: 38%	76	3	15 to 24	Light	45
Grim Shield	50-150	25	58	[20] Pal: 50% Ama/Asn/Bar: 45% Dru/Nec/Sor: 40%	70	2	14 to 20	Light	48
Pavise	68-78	25	133	[24] Pal: 54% Ama/Asn/Bar: 49% Dru/Nec/Sor: 44%	72	3	10 to 17	Heavy	50
Ancient Shield	80-93	25	110	[16] Pal: 46% Ama/Asn/Bar: 41% Dru/Nec/Sor: 36%	80	3	12 to 16	Medium	56