The Doctor's TARDIS (Silurian Earth)

The Doctor's TARDIS was a TARDIS from an alternate timeline generated by Mortimus. It was originally the TARDIS of the Third Doctor from that universe. That incarnation died, killed by the Silurians, and his regeneration was prevented by Mortimus.

The TARDIS shut down and died along with him. When Ace retrieved the TARDIS key from the Third Doctor's body, it had become isomorphically neutral, meaning anyone telepathically authorised could bond with it to activate and gain access to the TARDIS.

When dormant, the TARDIS's interior dimensions were only enough to contain the console. When Ace activated it by placing the TARDIS key in a slot in the console, it connected with her mind and recreated the interior dimensions. (PROSE: Blood Heat)

With his own TARDIS having been lost in a tar pit, the Doctor began to travel in this ship. Despite some problems involving the ship initially not trusting him, the Doctor eventually managed to get along with the ship until he gave it to the mysterious Muldwych, simultaneously reclaiming his original TARDIS from Muldwych after it escaped destruction in the alternate world via a Fortean Flicker (PROSE: Happy Endings).

Exterior
After the Doctor managed to repair it, this TARDIS had a working chameleon circuit. It could blend in with its environment. It became an Aztec idol in Mexico in 1487. When it arrived on the Titanic, it became a large, featureless crate. (PROSE: The Left-Handed Hummingbird) Ace plotted an exterior of the TARDIS using the keyboard inside the console: a 25th century Axmeister tank. On discovering this, the Doctor reset it to the TARDIS's control, upon which it disguised itself as a gingerbread cottage. (PROSE: Conundrum) In London, the Doctor materialised the TARDIS around Nelson's Column, then disguised it as the Column. Mortimus ruined the disguise, replacing parts of the column with the Statue of Liberty. (PROSE: No Future)

Finally it appeared as a tarot reader's tent. The Doctor decided to permanently "fix" it to appear as a police box from 1963, concluding that, while it was old-fashioned and out of date, he felt that the police box was him. (PROSE: No Future)

Interior
The interior was taken from Ace's mind when she first activated the TARDIS. There were laboratories, living quarters, a swimming pool, cloisters and libraries within the TARDIS's interior dimensions. She also created a new room for herself. (PROSE: Blood Heat)

The console room contained a Edwardian chaise longue and, within one of the roundels, a thermos of coffee. (PROSE: Blood Heat) There was also a basket chair and a hatstand in the console room. (PROSE: The Dimension Riders)

After Ace's departure, the interior took on the appearance of wood-panelled corridors with a 1930s style cage lift, plus an arboretum, a hospital ward, a complete indoor sports centre, a tennis court, a car garage, a water purification plant and a quarantine bay. (PROSE: Sanctuary)

Systems
The console had an emergency dematerialisation switch. This TARDIS was initially able to alert Ace and direct her attention to certain matters. (PROSE: Blood Heat)

The TARDIS had a working chameleon circuit (PROSE: The Left-Handed Hummingbird) until the Seventh Doctor permanently disabled it. (PROSE: No Future)

The TARDIS's state of temporal grace also functioned correctly, able to halt the missiles fired by the HMS Revenge at the Silurian's palace. (PROSE: Blood Heat)

It contained a Jade Pagoda, an escape pod for the TARDIS which contained basic flight systems. (PROSE: Sanctuary)

Personality
Initially the TARDIS did not trust the Seventh Doctor. It gave warnings, including sounding the Cloister Bell telepathically to the only one it did trust: Ace. (PROSE: The Dimension Riders) The TARDIS often became "sulky" when the Doctor was piloting it. While there was no day or night inside the TARDIS, it did dim the lights when it felt it should be night. (PROSE: The Left-Handed Hummingbird)