I am playing a Bladesinger in a Lost Mines of Phandelver campaign and I now have the Staff of Defense. The staff states that you get a +1 AC while holding the staff. If attack with my rapier while Bladesong is active, do I still get the +1 AC bonus from the staff for that round? Or do I need to attack with the staff to keep the AC bonus?
You are capable of dual wielding while using Bladesong. So you may hold both the Staff of Defense and your rapier at the same time, granting you the +1 AC while still being able to attack with the Rapier.
However, it should be noted that when it comes to casting spells, you need to have at least one hand free to cast any spell that has Somatic or Material components. This of course can be circumvented if you have the Warcaster feat or something else that ignores that rule.
The PHB state that you can perform the Somatic components with the same hand that is holding an arcane focus. And the staff is technically an arcane focus. So it should be ok. I just wanted to know what more experienced players and DMs thoughts are on this.
A spellcaster must have a hand free to access a spell's material components — or to hold a spellcasting focus — but it can be the same hand that he or she uses to perform somatic components.
You are capable of dual wielding while using Bladesong. So you may hold both the Staff of Defense and your rapier at the same time, granting you the +1 AC while still being able to attack with the Rapier.
Just nitpicking as you are essentially correct about holding the staff in one hand and the rapier in the other, but it's not really dual wielding and certainly not two-weapon fighting, as this requires light melee weapons and neither the staff nor the rapier are light.
It is a nitpick, but you are right. You would not be able to attack with both weapons unless you took the dual wielder feat.
The PHB state that you can perform the Somatic components with the same hand that is holding an arcane focus. And the staff is technically an arcane focus. So it should be ok. I just wanted to know what more experienced players and DMs thoughts are on this.
A spellcaster must have a hand free to access a spell's material components — or to hold a spellcasting focus — but it can be the same hand that he or she uses to perform somatic components.
You are correct when it comes to spells that require material components that have no cost or are not consumed by the spell. But if no Material component is required or the material components have a cost/are consumed, then you would need to have a free hand.
Edit: For further clarification on free hand requirements
I am playing a Bladesinger in a Lost Mines of Phandelver campaign and I now have the Staff of Defense. The staff states that you get a +1 AC while holding the staff. If attack with my rapier while Bladesong is active, do I still get the +1 AC bonus from the staff for that round? Or do I need to attack with the staff to keep the AC bonus?
You are capable of dual wielding while using Bladesong. So you may hold both the Staff of Defense and your rapier at the same time, granting you the +1 AC while still being able to attack with the Rapier.
However, it should be noted that when it comes to casting spells, you need to have at least one hand free to cast any spell that has Somatic or Material components. This of course can be circumvented if you have the Warcaster feat or something else that ignores that rule.
The PHB state that you can perform the Somatic components with the same hand that is holding an arcane focus. And the staff is technically an arcane focus. So it should be ok. I just wanted to know what more experienced players and DMs thoughts are on this.
It is a nitpick, but you are right. You would not be able to attack with both weapons unless you took the dual wielder feat.
You are correct when it comes to spells that require material components that have no cost or are not consumed by the spell. But if no Material component is required or the material components have a cost/are consumed, then you would need to have a free hand.
Edit: For further clarification on free hand requirements