Here's a list of many of the magical potions you can quaff (kinda like drinking a shot i guess) in the game. Where moer than one spell is listed it will cast all of them at the same time!  There are more to find so keep exploring!

Thanks to Latharia and Oyg for providing this info.

Learn more about the magical items in the game 

Potion Location* Level* Potion
Level**
Spell
Level**
Spells Flags**
 amber potion      1 30   cure light, armor  
 ambrosia  Olympus 1/28  41 29   heal, heal  invis, magic, anti-evil
 angel nectar      4 20  fly, cure poison, giant strength glow
 anti-cyclops elixir [1]  Elemental Canyon 1/16   5 16   invis  
 Argent [2]  Thrull shop 4/31       fly  
 azure  Thrull shop 5/29       detect invis  
 azure Whistling M.  47/59      stone skin, harm, cure critical  
 battlerager Kraig's Keep  13/19   16 18  giant strength, Warpsphere, cure poison  
 Black [2]  Moria 9/17       heal  
 black potion [3]      8 14   cure critical  
 black potion  Thalos 8/46   8 45  blindness, sanctuary, giant strength  invis, magic
 black potion  Wastelands Shop 4/21   2 21   detect invis  glow, magic
 blood red  Wamphyri 19/22      cure light, cure light, cure blindness  
 bloody potion      1 15  cure blindness, cure critical, giant strength  
 bloody red flask      20  armor, cure blindness  
 blue potion  Wastelands Shop 1/9   2 11   detect hidden, detect magic glow, magic
 bone marrow  keep 95/52      blindness, change sex, word of recall  
 bottle      31 12   cure critical, fire breath  
 bottle of cava  monestary 20/31  20-23 31   sanctuary, shield, armor hum
 bottle of fluid      10  poison  
 bottle of massage oil New Atlantis 22/11       refresh, cure critical, cure serious  
 bottle of soap      5 15   poison  
 breath of fresh air  Atlantis shop 2/201   1 201   Water breath  
 cherry red potion  Akaikiku (nippon) shop 5/28   2 30   detect invis  
 clear potion  caverns of the skull 24/15   29 16   know alignment, shield, sanctuary bless [5]
 clear potion  demonia shop 2/49   5 51   invis glow, evil, magic 
 clear potion  anapest shop 2/16       (none)  
 cloud white potion Akaikiku (nippon) shop 4/51   5 50   fly  
 Cloudy Green Potion  Old marsh 6/34   28 36   heal, faerie fire glow, hum 
 crimson potion  Whistling M. 46/50   45 49   curse, heal, armor  
 cyan potion  Isle of Quake  17/51  18 50   armor, bless  
 cyan potion  Westreen Shop 28/52       armor, bless  
 dark brown potion  Atlantis shop 1/23  5 21   cure critical, cure critical  
 dark red [2]  wyvern tower 16/9       cure blindness, cure critical  
 Death [2] port  2/9       teleport, teleport, teleport  
 deep blue [2]  port 26/10       cure serious  
 deep blue potion  demonia shop 2/23  4 22  real vision  glow, evil, magic
 deep red [2] ???  3/???       cure serious, cure blindness  
 Destruction [2] port   25/19      blacksphere  
 Effervescent [2]  High Tower of Sorcery 74/16       detect evil, detect invis, detect magic  
 empty container  Stratz shop ???  3 11   invis  
 engraved flask  port shop 4/10       control weather, cure serious, refresh  
 ethereal potion New Draconian Realm  33/49  54 49  sanctuary, pass door  
 ettin's blood Isles of the Pirate Lords 23/30   25 32   protection, stone skin  invis, magic
 Fabled [2] Rumania  5/51       curse, pass door, refresh  
 flagon of peach cordial Abbey  53/39       heal, heal  
 fizzy yellow potion      5 24   refresh  magic
 flannel potion  demonia shop 1/25   2 24   detect magic, shield  glow, evil, magic, anti-good
 flask filled with thick red liquid      20 21   cure light, cure light, cure blindness  anti-good
 flask of cranberry..  New Atlantis 2/21       cure critical, cure critical  
 flask of holy water  Dwarven Catacombs 12/23       bless  
 fuchsia potion haven   18/16 14 15   shield, remove curse  
 Green [2]   High Tower of Sorcery 74/21       blindness, teleport, cure blindness  
 green potion   Atlantis shop 4/15   3 14  detect invis  
 grey potion  CotS 12/20  14 18   stone skin, cure poison, cure light bless, noremove [5]
 holy grail Camelot  35/40  35-35 30  heal, armor, cure blindness  magic, anti-evil, anti-neutral
 holy potion      37 11   sanctuary, heal  
 icy bottle Hell   42/46  44 48  create water, create spring, faerie fog  
 jade green potion  Akaikiku (nippon) shop 5/30   1 30   shield, armored sphere  
 jar of blood  keep 53/49       teleport, remove curse, refresh  
 jar of formaldehyde great pyramid  12/10   13  cure light  
 Leaf-green [2] elven forest  19/31       energy drain, heal, cure critical  
 light blue potion      4 20   cure light, detect evil, infravision  
 luck potion  port shop 2/12       curse, heal, teleport  
 magenta potion  harpy clouds 12/11   11  armor, cure light, poison  anti-good
 Magical [2]  mythic castle 81/80       mana regen, mana regen, mana regen  
 maroon potion  Tournament 3/15   3 15   detect invis, detect hidden  glow, magic
 milky white [2]  High Tower of Sorcery 74/13       word of recall  
 Misty [2]  Dwarven Catacombs 8/9       pass door  
 mulberry extract  Milarbor shop 1/20   5 20   refresh, cure light, cure poison  magic
 murky green [2]  Old marsh 11/43       cure critical  
 nectar  Olympus 39/12   6 11   sanctuary, giant strength, armor  
 noxious grey potion  Wamphyri    11 19   bless, cure light, cure poison hum 
 Ocean-blue [2]  elven forest 19/31       sanctuary, bless, armor  
 old potion      9  teleport, teleport, teleport  magic
 Opal [2]  Orshingal 59/14       sanctuary, cure poison, heal  
 Orange [2]  Fire newts 15/10       heal, dispel evil, curse  
 orange potion  Thalos 6/20   8 20   detect hidden  invis, magic
 oxygen bubbles   New Atlantis 3/100       water breath  
 pearl white [2]  port shop 5/???       ???  
 pink potion  eastern desert 13/25   16 27   heal, remove curse  
plaid potion  demonia shop 5/49   4 51   armor, armored sphere  glow, evil, magic, anti-good
pool of green icky chunky barf      1  weaken newbie
potion      4 11   bless  magic
potion of protection  three 25/19  26 20   sanctuary, armor, bless glow 
potion of starlust      59 50   sanctuary glow 
potion of the lady     32 33  curse, cure poison, cure blindness  
Purple [2]  Moria 8/16      cure blindness, sanctuary  
 sage potion Atlantis shop 2/12 2  giant strength  
 shield of alar      4 19   armor, protection, stone skin  
Silver [2]  K-keep shop 3/20       cure blindness, cure poison, cure light  
silvery colored [2]  astral plane 8/20       detect invis, detect magic, detect poison  
skull shaped flask  keep 78/40      fireball, heal, heal  
slime of the enforcing eye     36 22   detect invis, heal, detect hidden  magic
small elixir  great pyramid 36/27  36 29   giant strength, sanctuary magic 
sparkling green potion  Yggdrasil 16/8   13 10   detect evil, detect invis, detect magic  glow, magic
starlust [4]  Rumania 58/51       sanctuary  
Strange [2]  Megamaze 1        blindness, curse, teleport  
striped potion  demonia shop 2/51  50   cure critical, cure critical  glow, evil, magic, anti-good
Super [2]  arachnos 24/14       cure poison, cure critical, cure critical  
sweet potato smoothie    New Atlantis  1/10      detect invis  
tiny vial of rainbow dreams      3 20   heal, heal, sanctuary  
tonic, acrid yellow  Mydgaard shop 4/10       detect invis  
tour port  9/31       teleport, teleport, teleport  
veridian Thrull shop 3/30       heal  
vermillion  Thrull shop 3/29       poison  
Vial-faerie magic  mystic castle 80/45      fly   
Vial-murky fluid  astral plane 6/15      blindness, shield   
Vial-murky grey  Wamphyri 30/18       cure light, cure poison  
Vial-squid ink     New Atlantis 3/49       emergency  
Violet [2]  port shop 1/10       giant strength  
White [2]  port 4/11       cure critical  
yellow flask port  27/10      giant strength, faerie fire, cure light  
yellow potion     19 14  giant strength  magic

 * info provided by Latharia       ** info prpvided by Oyg

[1] Larathia listed both “anti-cyclops elixir” and “elixir: anti-cyclops”. The first of these is recorded here.

[2] Larathia misses “potion” of the end of the name

[3] Oyg had a duplicate row for the black potion giving ‘cure critical’ 

[4] may be same thingas potion of starlust

[5] bless as a flag - check this is right