|Season 7, Episode 6|
|Premiere date:||September 3, 2015|
"The Dome Experiment"
"Birthday Gift" is the sixth episode of season seven (and one hundred eighty-seventh overall) of Regular Show. It first aired on September 3, 2015.
In spite of a bad track record, Rigby is determined to give Mordecai a great birthday gift.
It all started when Mordecai, Rigby, and Skips was on the roof fixing and replacing the tiles. Rigby makes a birthday rap for Mordecai since today is his birthday. Then Rigby goes inside the house to get Mordecai his present which was in the bathroom cabinet and it's shaped like a mug. Before he goes out, he tells himself he gives the best gifts but outside Rigby heard Mordecai telling Skips that Rigby is actually the worst for getting gifts because whenever he gets Mordecai a birthday gift, he never put any thought into them and if he does, they're usually gifts for himself but Mordecai said it's fine because he's used to it. A flashback shows a younger Rigby singing the same birthday rap but taking the gifts he gives to a younger Mordecai like donuts, a t-shirt that said "Mordecai's friend", and a birthday card with a "I.O.U. card on it". After the flashbacks, Rigby doesn't think his gifts are that bad until he opened Mordecai's gift which was a mug that said "World Greatest Rigby". Realizing Mordecai is right, he decides to get Mordecai a better birthday gift.
He goes into the kitchen to think about what Mordecai likes. Hours later he remembers that Mordecai likes videos games so he goes to the video games store but the video games cost 50 and 49 dollars. He leaves and goes to the coffee shop, where Eileen gives little consolation. A man introducing himself as Zaxon overhears them and claims that Rigby can simply create a video game with his own mind using his advanced "Z.I.P.G.I.D.Z." (acronym for "Zaxon's Intelligent Player-to Game Interface Designed-by Zaxon") technology and shows them a video of it. Eileen criticizes Zaxon's video but he and Rigby both leave before she is heard.
At Zaxon's house the two conduct varies physical and mental tests on Rigby. He passes the physical tests with "off the chart" results but his I.Q. results from the mental tests are "so low they aren't even on the charts". They use two helmets to transport themselves into Rigby's head. There he can make the video game with his mind, but due to Rigby's low I.Q., Zaxon warns that there will be "bugs". He also warns that the helmets can kill. They enter a digital world resembling the park with Mordecai and Skips on the roof with a birthday cake. Rigby attempts to create simple obstacles to overcome, but accidentally creates an extremely dangerous and elaborate track to the house. The "bugs" mentioned earlier (now revealed to be giant red killer ants) start chasing Zaxon and Rigby through the game as they make their way to the house. As they climb up a steep obstacle Zaxon pulls out a sword and begins to fight the bugs to stall for Rigby. He is overwhelmed by the sheer number of them and is seemingly killed. The bugs continue to pursue Rigby and corner and swarm him on the house, but Rigby fights them off and finally reaches the end. Rigby emerges from the simulation with a seemingly dead Zaxon (who reveals he is only "video game dead") and the video game (titled "Cake Quest") is made. Rigby makes it home to Mordecai (who angrily tells Rigby he went to the bathroom and never came back for the party) and gives him the video game. It is an awful and simple game that Mordecai easily beats, thus confirming to him that Rigby really did make it. But he still says it's the best gift he ever gave him.
- When Rigby's video game looks awesome in his mind but in reality was bad may be a reference to "Men in Uniform" when online the uniforms look awesome but in reality were awful.
- Eileen says "Who would actually believe that? ... Except my boyfriend" is continuing from "Dumped at the Altar" when Rigby said he and Eileen were dating and "Dumptown USA".
- Rigby shooting fire out of his hands heavily resembles Goku's signature Kamehameha from the Dragon Ball franchise. Even a sound effect from the series is played.
- Tendindo is an obvious parody of Nintendo.
- The shape of the HQ is also similar to the shape of the NES (Nintendo Entertainment System)
- What happened at Tendindo is the opposite of what happened at Nintendo, where Gunpei Yokoi, previous janitor of Nintendo, was promoted after coming up with the idea of the Gameboy
- Sam Marin is credited in this episode despite him not voicing anyone in it.