Aa'sra Tower

Standing in ruins at the southern edge of Ironwood Forest, Aa'sra Tower is the last remaining legacy of a long-ago Artificer Mage specializing in animating constructs and attempting to create mechanical intelligence. One of her final works remains guarding the tower, keeping the crumbled stone walls safe from Harpies, Ratlings, and others with curiosity or looting on their minds.

The Tower

Visible to travelers in the Ironwood Forest as a tall, grey, weathered stone structure peeking through the trees, the structure can barely be considered a tower as such. In a clearing within the southern reaches of the forest, the tower consists primarily of a wide stone stairway rising to a wide circular foundation. The walls of the first level are intact, though there is no door. Pieces of the walls themselves reach approximately two to three stories high, but are only actually intact for about half of the circumference of the tower. There is a set of steps along one wall inside the tower, but it does not have any actual floors to climb to.
Inside, there is some ruined furniture, an extremely faded and damaged wall painting of Lasair, and a pristine suit of plate armor standing against the wall, flanked by two gleaming scimitars mounted upon the wall behind it.

The plate armor is a suit of Animated Armor; the swords Flying Swords [5E Monster Manual, p.19-20.] They will become animated and attack any living creatures that attempt to touch them. They will pursue 50 yards away from the tower before returning to their standing locations. If defeated, the preserving magic holding them will collapse in a puff of light, the metal falling to rust.

The Guardian

Aa'sra's last construction before her disappearance was a marvel. An autonomous, mechanical, magically-imbued construct, the guardian would be capable of protecting a site against intruders while allowing invited guests or those of a specific order to gain access. The guardian is simple in appearance: a floating rectangle of brass-and-gemstone construction. Looking closely at it would reveal fine filligree work along its surface, as well as what appears to be seams that divide it up into four cubes.
The guardian circles the tower (hovering in the air and moving at walking speed). If a creature approaches, it will call out, in a grinding mechanical voice from its internals: "IDENTIFICATION". If it is not given satisfactory identification matching its criteria, it will attack any creature that approaches to within 50 feet of the tower. If sufficient damage is dealt to it, it will break in half - becoming two double-cube constructs which attempt to flank an attacker. Finally, those can break down further, creating a total of four cubes, each capable of attacking individually or as a group. Each cube that makes up the whole fights with magical force beams emitting from the gemstones within its surface, or with pistons thrusting from within.

The Guardian is created from the Modrons [5E Monster Manual, p.224-226]. Start with a Quadrone, then two Duodrones, then finally four Monodrones. "Reskin" the ranged attacks as magical force attacks. In addition the constructs do not speak Axiomatic, only a very small subset of High Common and/or Arcana. This particular Guardian's desired form of Identification is a signet ring belonging to any member of the Mages; any bearer of such a signet ring will be ignored by the Guardian, and anything that attacks such a bearer (including the animated armor/weapons inside the tower) will be subsequently attacked by the Guardian.

Note that this protection does not extend to party members - only the bearer of the ring itself is safe!

If defeated, the Guardian will yield gemstones of approximately 300gp in value.

Legacy

Within the tower, easily found by anybody who passes the Guardian (and ignores or defeats the animated armor), a wizard's spellbook can be found laying within the clutter. This is a spellbook compiled by Aa'sra herself and will bear her rune if examined with a Detect Magic spell. The book is magically locked and will only open for someone with knowledge of its passphrase (or with Dispel Magic). An artificer could be found within the Mage Islands who would have been familiar with Aa'sra (as a student, teacher, or other confidant).
If the spellbook is able to be opened, it will contain details on the design and construction of the Guardian. This would certainly be of great value to a member of the Artificer Mage School.

Type

Tower