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Hotel Mario sees Mario and Luigi go through several Koopa Hotels to rescue Princess Toadstool, who gets kidnapped seven times, and along the way shut all the doors in the Hotels. It's mostly notorious for its cutscenes of questionable quality, which are frequently used in YouTube Poops.
While this wasn't the only Mario game developed for the ill-fated CD-i (the others being Super Mario's Wacky Worlds and Mario Takes America), it was the only one that got released. Whether that's a good thing depends on who you ask.
The game is missing files for Level 6, as can be seen through the file list:
L0_av.rtf (Demo File) L0_dat.rtf (Demo File) L1_am.rtf (Hotel 1 Music file) L1_av.rtf (Hotel 1 Graphics file) L1_dat.rtf (Hotel 1 Enemy Data) L2_am.rtf (Hotel 2 Music file) L2_av.rtf (Hotel 2 Graphics file) L2_dat.rtf (Hotel 2 Enemy Data) L3_am.rtf (Hotel 3 Music file) L3_av.rtf (Hotel 3 Graphics file) L3_dat.rtf (Hotel 3 Enemy Data) L4_am.rtf (Hotel 4 Music file) L4_av.rtf (Hotel 4 Graphics file) L4_dat.rtf (Hotel 4 Enemy Data) L5_am.rtf (Hotel 5 Music file) L5_av.rtf (Hotel 5 Graphics file) L5_dat.rtf (Hotel 5 Enemy Data) L7_am.rtf (Hotel 7 Music file) L7_av.rtf (Hotel 7 Graphics file) L7_dat.rtf (Hotel 7 Enemy Data) L8_am.rtf (Hotel 8 Music file) L8_av.rtf (Hotel 8 Graphics file) L8_dat.rtf (Hotel 8 Enemy Data)
The L6_ files are missing, which suggests that Hotel Mario was originally going to follow the Super Mario Bros. 3 and Super Mario World formula by having a Hotel for each of the Koopalings and one for Bowser. As a result, Iggy lacks a unique Hotel and is instead fought on the final floor of the game, right before the fight with Bowser.
An early version of the Stage 1 title card that is more simplistic then the final one, stored in L0_av.rtf. One exists for each stage in the file. Other than the font and background, it also says to "press a button" to enter the level, rather than specifying the 1 button.
Help dialogue from an early version of the game, although the instructions seem to be explaining the final. The voice actor sounds nothing at all like Mario's actor from the final, suggesting that this was a placeholder.
An early version of the cutscene audio that plays when you beat Roy. It does not use the voice actors from the final, although they are much closer than the voice actor from the help dialogue; they seem to be heavily based on Walker Boone and Tony Rosato's takes on the brothers from the Mario cartoon series airing at around the same time. Oddly enough, this is stored in the data for the final level, not Roy's. There is no known cutscene data.
Stages 2, 3, 4, and 5 have an alternative, longer "stage clear" theme that goes unused.
This music was eventually used at the end of the "Toasters" cutscene accessible in Stage 2.
For some reason, this stage's alternate clear music is the same as the one used in Stage 7, but with an added echo.
The stomp effect sprite has what appears to be a peace symbol inside. Since this sprite is shown for only a split second in-game, it is not easily seen.
If the CD-i's clock is set to specific days, the "HERE WE GO" screen will be replaced by a special message.
Special events in an American year.
HAPPY NEW YEAR
Displays on January 1, which is New Year's Day.
HAPPY VALENTINES DAY
Displays on February 14, which is Valentine's Day.
ITS HOLLIES BIRTHDAY
Displays on February 17. Likely refers to Hollie S. Lohff, the play consultant for Hotel Mario.
DO NOT FORGET MOTHERS DAY
Displays on the second Sunday of May, which is Mother's Day.
SCHOOLS ALMOST OUT
Displays on May 31, when most schools began Summer vacation (at the time).
HAPPY FATHERS DAY
Displays on the third Sunday of June, which is Father's Day.
HAPPY FOURTH OF JULY
Displays on July 4, which is America's Independence Day (often referred to as the "Fourth of July").
READY TO GO BACK TO SCHOOL
Displays on August 31, when most schools went back into session (at the time).
Displays on October 31, which is Halloween. Also a pretty good summary of the whole game.
HAPPY TURKEY DAY GOBBLE GOBBLE
Displays on the fourth Thursday of November, which is Thanksgiving. Turkey is commonly served at Thanksgiving dinners.
Displays throughout December, which is the month of Winter holidays.
HAPPY NEW YEAR
Possibly a duplicate of the first string, but December 31 is New Year's Eve.
A little different from the English one, with events special to France.
"Happy New Year." Displays on January 1, which is New Year's Day.
ALLONS CHERCHER LA FEVE
"Let's find the charm." Displays in late January, a time of year where in France the people eat some "Galette des Rois" (King's Pie) and there is a charm hidden in the pie.
C'EST LA SAINT VALENTIN
"It's Valentine's Day." Displays on February 14.
ON SE DEGUISERA POUR LE MARDI GRAS
"We'll be dressing up for Mardi Gras." Carnival celebration in France.
OU SONT CACHES LES OEUFS
"Where are the eggs hidden?" Likely referring to Easter.
BONNE FETE MAMAN
"Happy Mother's Day, Mom!" Displays on the last Sunday of May, which is Mother's Day in France.
L'ECOLE EST BIENTOT FINIE
"School is almost over." Displays on May 31, when most schools began Summer vacation (at the time).
BONNE FETE PAPA
"Happy Father's Day, Dad!" Displays on the third Sunday of June, which is Father's Day in France.
ALLONS ENFANT DE LA PATRIIIIEEE
"Arise, children of the Fatherland." (Taken from the French national anthem "La Marseillaise", although "ENFANT" should be "ENFANTS" due to the plural grammar rule.) Displays on July 14, which is France's national celebration.
PREPAREZ VOS CARTABLES
"Prepare your schoolbags." Referring to returning to school. Displays on August 31, when most schools were ending Summer vacation (at the time).
"Merry Christmas." Appears on December 25.
"Happy New Year", possibly a duplicate of the first string.
FPD on December 6, 1993
Stored in the file "biblio", "FPD" likely means "Finished Project Date", so this file probably just exists to mark the date the game was finished.
The French version has completely different text:
The PHILIPS Interactive Media Centre Development Team in Hasselt - Belgium, made a FRENCH conversion of " HOTEL MARIO ". Engineering Bob Deblier Eddy Paulissen Production Coordinator Annet Daems Hugo Paulissen **************************************
In the French intro, Bowser's laugh has no reverb.
The French cutscenes are completely dubbed. Unfortunately, aside from being poorly dubbed the French speech has many errors, like Bowser being called "Boswor".