For the first question I guess you mean if you'd still get the advantage from raging while using wisdom (because obviously you could use wisdom without getting the advantage, nothing in the rage prevens that), and I would say would - arms of the astral self allow you to use your wisdom modifier, but it's still a strength check/save.
For the second question, the answer is no. Dedicated weapon specifically says "The weapon must be a simple or martial weapon", and a natural weapon is neither. Your DM might allow you to ignore this restriction, but that would definitely not be RAW.
Edit: oops, got this one wrong. The weapon from form of the beast counts as a simple weapon for you, so it does qualify.
For the third question again the answer is no, rage requires that you make a weapon attack using strength to get the bonus, so a weapon using dexterity, for whatever reason, clearly doesn't qualify (and unarmed strike also doesn't qualify, whatever the ability you use)
With your Astral Arms active, you still have advantage on STR checks/saves, even if you use your WIS stat to calculate those rolls.
You don't actually need the Dedicated Weapon feature to use your Form of the Beast natural weapons as monk weapons. The Beast natural weapons are treated as Simple Melee Weapons by you... a Monk's Martial Arts feature applies to any Simple Weapon that lacks the Heavy or Two-Handed property. I think the more complicated question is whether you can use them to make unarmed strikes, since they are technically part of your body.... I think they can't be used in that way, but it's one of those weird gray areas where you could see a lot of conflict between RAW and RAI.
Finally, the Barbarian's Rage feature overtly states that the damage bonus only applies if you use STR to make an attack. However, the Monk's Martial Arts feature states that they MAY use DEX instead of STR for certain attacks... you can still use all your Monk features even if you decide to build a STR-based monk. The same even applies to the Astral Arms... they give the option to use WIS for your attacks, but you can still use your STR score instead if you really want to.
So I am in this game and I have this Astral monk, and I am planning to multi-class into barbarian.
I want to know what happens with these combinations.
Rage - for strength checks and saves can I use wisdom if I have Astral chains up?
Can I use the Dedicated Weapon feature on the simple weapon given by the beast barbarian sub class? (bite, claws, tail)
If I use a monk weapon (like a quarter staff) while raging do I get the rage weapon bonus of I use my Dex because of martial arts?
For the first question I guess you mean if you'd still get the advantage from raging while using wisdom (because obviously you could use wisdom without getting the advantage, nothing in the rage prevens that), and I would say would - arms of the astral self allow you to use your wisdom modifier, but it's still a strength check/save.
For the second question, the answer is no. Dedicated weapon specifically says "The weapon must be a simple or martial weapon", and a natural weapon is neither. Your DM might allow you to ignore this restriction, but that would definitely not be RAW.
Edit: oops, got this one wrong. The weapon from form of the beast counts as a simple weapon for you, so it does qualify.
For the third question again the answer is no, rage requires that you make a weapon attack using strength to get the bonus, so a weapon using dexterity, for whatever reason, clearly doesn't qualify (and unarmed strike also doesn't qualify, whatever the ability you use)
With your Astral Arms active, you still have advantage on STR checks/saves, even if you use your WIS stat to calculate those rolls.
You don't actually need the Dedicated Weapon feature to use your Form of the Beast natural weapons as monk weapons. The Beast natural weapons are treated as Simple Melee Weapons by you... a Monk's Martial Arts feature applies to any Simple Weapon that lacks the Heavy or Two-Handed property. I think the more complicated question is whether you can use them to make unarmed strikes, since they are technically part of your body.... I think they can't be used in that way, but it's one of those weird gray areas where you could see a lot of conflict between RAW and RAI.
Finally, the Barbarian's Rage feature overtly states that the damage bonus only applies if you use STR to make an attack. However, the Monk's Martial Arts feature states that they MAY use DEX instead of STR for certain attacks... you can still use all your Monk features even if you decide to build a STR-based monk. The same even applies to the Astral Arms... they give the option to use WIS for your attacks, but you can still use your STR score instead if you really want to.
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