Polymorph self - Mindflayer/Illithid

[Hoihe]

Ahoy!

I wonder if polymorphing into this form allows the character to use psionic devices. (Such as a gold diamond used to store and unleash psionic energy. The goal is to make it drain psionic energy from someone). My reasoning is, psionics is an inborn ability of Illithid and I'd assume psionic devices would recognise the race and work, sort of like Use Magic Device allows you to wear race items/class items but in form of a makeshift Use Psionic Device in form of literally altering one's race temporarily in order to fool the device.

Thanks in advance!

I'd assume DM Galadriel has the final say in this, since the gold diamond is his/Her plot item.

[Maecius]

In general, the answer is no. For two reasons, really:

1.) We ask that players not import pen-and-paper content that cannot be mechanically reproduced outside of DM events. It's part of the "play what's on your sheet" philosophy, and it's main purpose is to ensure that everyone is treated fairly and that metagaming is kept to a minimum.

And, 2.) the polymorph spell actually functions as follows:

The subject gains the Strength, Dexterity, and Constitution scores of the new form but retains its own Intelligence, Wisdom, and Charisma scores. It also gains all extraordinary special attacks possessed by the form but does not gain the extraordinary special qualities possessed by the new form or any supernatural or spell-like abilities.

Note that the ability of mind flayers to use "psionics" is considered a spell-like ability in the Monstrous Manual.

As a final word, DMs are able to overrule the above in their own events, if they so desire. So if Galadriel wants to run with your idea, that's between Galadriel and yourself. But as per the canon Lore, it's not feasible.