Season 4 premiered on April 2, 2012. Episode titles were posted on the Frederator Blog in March 2012.[1]
Writing of the season had started by May 2011.[2] The season saw the premiere of the 100th episode of the series, "The Hard Easy" (previously titled "Prince Huge"). Adam Muto reported that characters not seen since the earlier seasons would return, with The Earl of Lemongrab, Magic Man, the Lich, Hunson Abadeer and Neptr being confirmed to return. Prior to the season's airing, Adam Muto said that Marceline's backstory would be explored further, and Jeremy Shada also mentioned that Marceline and Ice King would sing together,[3], which took place in the episode "I Remember You." The season featured guest voices by Donald Faison, George Takei, Erik Estrada, Andy Milonakis, Emo Phillips, Bobcat Goldthwait and Susie Essman. The season featured one complete two-parter ("Return to the Nightosphere" and "Daddy's Little Monster"), however the season's introductory episode was a continuation of the season 3 finale, and the season 4 finale continued into season 5's two-part opening episode.
| No. overall | No. in season | Title card | Title | Viewers (in millions) |
Prod. code | Airdate |
| 79 | 1 | 
|
"Hot to the Touch" | 2.655[4] | 1008-082 | April 2, 2012 |
| Finn goes on a quest to prove Flame Princess isn’t really evil, but ends up trying to stop Flame Princess from taking over the Goblin Kingdom. | ||||||
| 80 | 2 | 
|
"Five Short Graybles" | TBA | 1008-079 | April 9, 2012 |
| A series of short stories all centered around the five senses. | ||||||
| 81 | 3 | 
|
"Web Weirdos" | TBA | 1008-081 | April 16, 2012 |
| When Finn gets trapped in a giant spider web, he ends up playing marriage counselor to a couple of grumpy arachnids. | ||||||
| 82 | 4 | 
|
"Dream of Love" | TBA | 1008-080 | April 23, 2012 |
| Tree Trunks is courted by an oinking suitor, but much to Jake's dismay, this interferes with her baking habits. | ||||||
| 83 | 5 | 
|
"Return to the Nightosphere" | TBA | 1008-085 | April 30, 2012 |
| Marceline’s dad banishes Finn and Jake to the Nightosphere, and it stinks. Literally. | ||||||
| 84 | 6 | 
|
"Daddy's Little Monster" | TBA | 1008-086 | April 30, 2012 |
| Finn and Jake attempt to rescue Marceline and find out what's making her behave so strangely. | ||||||
| 85 | 7 | 
|
"In Your Footsteps" | TBA | 1008-083 | May 7, 2012 |
| Finn and Jake befriend a bear, but what are the bear's intentions? | ||||||
| 86 | 8 | 
|
"Hug Wolf" | TBA | 1008-084 | May 14, 2012 |
| Finn discovers a hug wolf and goes through a strange transformation. Becoming a hug wolf himself! | ||||||
| 87 | 9 | 
|
"Princess Monster Wife" | TBA | 1008-088 | May 28, 2012 |
| The princesses are strangely losing body parts. So, Finn and Jake investigate. | ||||||
| 88 | 10 | 
|
"Goliad" | TBA | 1008-087 | June 4, 2012 |
| Realizing her mortality, Princess Bubblegum creates an immortal replacement. | ||||||
| 89 | 11 | 
|
"Beyond this Earthly Realm" | TBA | 1008-089 | June 11, 2012 |
| When Finn finds a porcelain lamb, it transports him into the spirit world and only the Ice King can help get him out! | ||||||
| 90 | 12 | 
|
"Gotcha!" | 2.392[5] | 1008-090 | June 18, 2012 |
| In order to do research for her tell-all memoir about men, Lumpy Space Princess goes undercover working for Finn and Jake. | ||||||
| 91 | 13 | 
|
"Princess Cookie" | TBA | 1008-091 | June 25, 2012 |
| Finn and Jake are called to solve a Candy Kingdom hostage crisis when a rogue cookie takes over. | ||||||
| 92 | 14 | 
|
"Card Wars" | TBA | 1008-092 | July 16, 2012 |
| Finn and Jake play Card Wars, an epic card game. | ||||||
| 93 | 15 | 
|
"Sons of Mars" | TBA | 1008-093 | July 23, 2012 |
| Jake becomes a copy of Magic Man after a run-in with him. | ||||||
| 94 | 16 | 
|
"Burning Low" | 3.504[6] | 1008-094 | July 30, 2012 |
| Princess Bubblegum may be jealous when Finn starts hanging out with Flame Princess. | ||||||
| 95 | 17 | 
|
"BMO Noire" | TBA | 1008-095 | August 6, 2012 |
| BMO tries to find Finn's sock. | ||||||
| 96 | 18 | 
|
"King Worm " | TBA | 1008-096 | August 13, 2012 |
| All of Ooo appears in Finn's vivid dream.[7] | ||||||
| 97 | 19 | 
|
"Lady & Peebles" | 2.754[8] | 1008-098 | August 20, 2012 |
| Princess Bubblegum and Lady Rainicorn search for a missing Finn and Jake. | ||||||
| 98 | 20 | 
|
"You Made Me" | TBA | 1008-099 | August 27, 2012 |
| When a creepy sleep-peeping Lemongrab upsets Princess Bubblegum with his creepy ways, Finn and Jake need to tend to some issues in the Outer Realm. | ||||||
| 99 | 21 | 
|
"Who Would Win" | TBA | 1008-097 | September 3, 2012 |
| Finn and Jake challenge a monster to a fight but end up battling each other.[9] | ||||||
| 100 | 22 | 
|
"Ignition Point" | 2.256[10] | 1008-101 | September 17, 2012 |
| Finn and Jake sneak into the Fire Kingdom and are caught in a family feud.[11] | ||||||
| 101 | 23 | 
|
"The Hard Easy" | 2.643[12] | 1008-100 | October 1, 2012 [13] |
| Mudscamps seek protection from the Mega Frog who's attacking their swamp. | ||||||
| 102 | 24 | 
|
"Reign of Gunters" | 1.845[14] | 1008-102 | October 8, 2012[15] |
| Gunter and his doppleganger cause chaos in Ooo.[16] | ||||||
| 103 | 25 | 
|
"I Remember You" | 2.535[17] | 1008-103 | October 15, 2012 |
| Ice King and Marceline bond over memories. [18] | ||||||
| 104 | 26 | 
|
"The Lich" | 2.589[19] | 1008-104 | October 22, 2012 |
| A visit from the Lich sheds light on Land of Ooo's secrets. | ||||||
- ↑ http://adventuretimeart.frederator.com/post/19253533144/season-four-episode-titles-here-we-go-as-with
- ↑ http://twitter.com/#!/buenothebear/status/65160425511202816
- ↑ http://www.youtube.com/watch?v=Mnn8X6ChSL0&feature=relmfu
- ↑ TV by the Numbers 04/04/2012
- ↑ http://tvbythenumbers.zap2it.com/2012/06/19/monday-cable-ratings-pawn-stars-wwe-raw-american-pickers-love-and-hip-hop-atlanta-single-ladies-hardcore-history/138631/
- ↑ Viewership for Week ending August 5, 2012
- ↑ http://tvlistings.zap2it.com/tv/adventure-time-king-worm/EP012462650155
- ↑ Viewership for August 20, 2012
- ↑ http://www.tvguide.com/tvshows/adventure-time-2012/episode-21-season-4/who-would-win/304498
- ↑ Viewership for September 17, 2012
- ↑ http://www.tvguide.com/tvshows/adventure-time-2012/episode-22-season-4/ignition-point/304498
- ↑ Viewership for October 1, 2012
- ↑ http://www.nickandmore.com/2012/09/17/cartoon-network-announces-20th-birthday-plans-for-october-2012/
- ↑ http://sonofthebronx.blogspot.com/2012/10/cartoon-network-ratings-october-8-14.html
- ↑ http://www.cartoonnetwork.com/schedule/index.html?atclk_gn=gn_link_tvschedule
- ↑ http://www.tvguide.com/tvshows/adventure-time-2012/episode-24-season-4/reign-of-gunthers/304498
- ↑ Viewership for October 15, 2012
- ↑ http://www.tvguide.com/tvshows/adventure-time-2012/episode-25-season-4/i-remember-you/304498
- ↑ Viewership for October 22, 2012