Here is the full list of all 47 Doctor Who: The Eternity Clock achievements.
Complete the game
Complete the game in under 300 minutes
Defeat the Emperor of the Daleks
Shoot the Emperor Dalek in the eyestalk
Send the Dalek Supreme to the Arctic
Finish time-locked London in under 20 minutes
Find the TARDIS inside the Dalek time lock
Defeat the Silence and steal their time capsule
Activate the crane winch in Old St. Pauls
Outwit the Strategist Dalek
Discover the statue in the Elizabethan Quadrangle
Press 10 TARDIS console buttons
Defeat Vekkis
Complete a Data Link puzzle in under 60 seconds
Wake up River in the tomb
Collect the Stasis Field Generator in the Silence Base
Sonic disarm 5 Silurians
Collect 20 diary pages
Collect 20 hats
Lower the drawbridge in Old London Bridge
Complete a Time Corridor in under 2 minutes
Re-route the thermionic consoles in the Cyberfactory
Collect 10 hats
Open the security door in the office block
Complete a Re-Router puzzle in under 60 seconds
Re-route the gas pipe plans in Victorian London
Collect 10 diary pages
Defeat the Cybermen in the Underground refugee camp
Collect 5 hats
Collect 5 diary pages
Beat the Cybermen to the Underground refugee camp
Scan 10 objects
Use the gold bullion crate to smash your way out of the Bank of England
Escape the Stormcage without being detected
Kiss 6 Stormcage guards
Escape Stormcage in under 8 minutes
Stun 5 Cybermen
Finish the Cyberfactory in under 20 minutes
Finish "Return to Victorian London" in under 15 minutes
Outwit the Silence without being checkpointed
Quick-shoot 5 Daleks
Power-shoot 5 Daleks
Complete a Mind Map puzzle on Medium or Hard in under 60 seconds
Complete the game on Medium difficulty
Complete the game on Hard difficulty
Collect all of the diary pages
Collect all of the hats