
Castlevania and Contra are two of Konami's biggest side-scrolling platform franchises. They reference each other from time to time, and are sometimes bundled together side by side.
Examples[]
In Contra: Hard Corps, in the Junkyard stage, before destroying the first door, climb the wall and you will reach a hidden section where you will meet a Mysterious Character. He will ask if you want to do money in the Arena. Respond "YES" and you will enter a room where you'll be tested with a series of miniboss fights.
The first boss you will fight is Simondo Belmont, a parody of both Simon Belmont and Masato Shimon. The theme that will play in the background is SIMON 1994RD, a remix of Vampire Killer.
Arthroverta a boss from Castlevania: Order of Ecclesia, resembles Kimkoh.
When booting up Contra: Operation Galuga, if the player also has a save file of the Castlevania Anniversary Collection, they are rewarded with the "Vania Mix" soundtrack for Arcade and Challenge modes. The text used for this notification is borrowed from the famous Easter egg in Metal Gear Solid (also by Konami), where Castlevania: Symphony of the Night is read on the memory card.
Gallery[]
Konami Collector's Series: Castlevania & Contra[]

Konami Collector's Series: Castlevania & Contra is a compilation of five classic NES Konami games ported to the PC. Three are from the Castlevania series and two from Contra.
The games included are:
Contra Advance: The Alien Wars EX[]

BradyGames packaged its Contra Advance: The Alien Wars EX strategy guide with its Castlevania: Harmony of Dissonance guide.
Contra ReBirth[]
The second game in Konami's "ReBirth" series made for WiiWare. It was later followed up with Castlevania: The Adventure ReBirth.
Trivia[]
- Coincidentally, both franchises contain the letter C in the beginning of their respective names and are commonly enlarged within their respective title logos. Both titles also end with the letter "a".