Horrible Heartbeat (戦慄の鼓動 Senritsu no Kodō?), also known as Shivery Beat or Pulse of the Terror, is a music theme originally composed for Contra. It is the background theme for the last stage of the game, Alien's Lair. Since then it has become a widely popular theme and diverse arrangements have appeared throughout the series, as well as in promotional media.
Audio[]
| Title | Game | Stage | Audio | Usage |
|---|---|---|---|---|
| Horrible Heartbeat | Contra (arcade) | Alien's Lair | BGM | |
| Shivery Beat | Contra (NES) | Alien's Lair | BGM | |
| Contra: Operation Galuga (Retro Mix) | Alien Hive | |||
| Shivery Beat | Contra (MSX2) | Alien's Zone Vicious Space |
BGM | |
| Fighting Jungle 2 | Wai Wai World 2: SOS!! Parsley Castle | World 4 | Alien King boss fight | |
| Alien Lair | Operation C | Area 5 | Hayanos 614 and Black Viper boss fights | |
| Heart Battle | Contra 4 | Alien Hive | Gomeramos King boss fight | |
| Contra: Operation Galuga (WayForward Mix) | Ruins | Beowulf miniboss fight | ||
| Horrible Heartbeat | Contra ReBirth | Red Falcon Megalith | BGM | |
| Shivery Beat | Contra: Evolution | Alien's Lair | BGM | |
| Contra Returns | Stages 2-6, 5-3, 5-4, 12-5, 13-1, 13-4, 13-6, 15-3, 15-4 | BGM | ||
| What they were Growing in the Lab | Contra: Operation Galuga | Escape Ship (inside Java section) | BGM | |
| Alien Slayer | Contra: Operation Galuga (Retro Remix) | Alien Hive | BGM |