Consider the Staff of Ruin. It was introduced in the same bookThe applicable rules:
Magic Item level: You have to have the magic item on your person for it to work.
Slotted item level: You have to hold/wield an implement/weapon for it to work. (Rules Compendium). If you have a weapon, these two rules have to collide, and the narrower wins.
2a. There is no option to satisfy (1) and (2) simultaneously.
2b. In case of an implement, you have to hold it.
2c. In case of a solitaire, rule(2) does not apply, so it work from your pocket as well.
Weapons level: You have to attack with weapons to use its attack properties. (Adventurer's Vault). If you attack with the weapon, this and rule(2) has to collide, and the narrower wins.
3a. There is no option to satisfy (1) and (2) simultaneously. You either attack, or you do not.
3b. In case of an attack property, you have to make the attack with this weapon.
3c. In case of a non-attack property, so it is enough to hold it.
Enchantment level: Vanguard gives you 1d8 on a charge. This rule could contradict with rule(3), depending on which weapon you use to attack.
4a. In case you use the Vanguard weapon for attacking, there is no collision of rules.
4b. You can not force rules into collision. So the only option is (4a).
Disregarding rule (4b) could cause the following problem:
- My power says I can shift 1 (rule A).
- But here is difficult terrain, and difficult terrain costs more to shift (rule B).
If you could force rules into collision, (A) would win, as it is more specific, so you could shift whenever and originally gave an item bonus whetherwherever you used it to for the attack or notwant. Later it was errataed to limit the bonus to attacks made with itSo rule (4b) from above is actually RULE 0. Vanguard weapon was never
In my opinion two things make a rule offical:
- It was published by WotC. Adventurer's Vault was.
- The rule was not errataed. This part of AV was not.
Otherwise we could start questioning PHB itself, as it is the most errataed publication of WotC, because the bonus did not apply to other attacks in the first placeso it must be absolutely wrong.
