The hidden frogs are static frogs sitting on red books (which are also available as standalone models), they explode when thrown or dropped, and when you throw it at a Korean, it knocks them down for some reason. When you pick up your first frog, Psycho will either say, "It's a Kalmon! I found it," or "It's a Calvin! I found it!" All the other frogs you pick up, except the last one, will have Psycho say, "Well..." The last frog will have Psycho say, "Oi! Not bad! Back to work!" if he collects all frogs before. After collecting all 7 frogs, it unlocks a bonus ending where the container is replaced by a giant frog. As O'Neil touches the frog to look at it, it responds by cloaking. When Colonel Lee aims his pistol at O'Neil, the frog has changed back into the container.
Where to Find ThemEdit
1. Call me Ishmael: After completing the objective, "Join up with Sierra airstrike team" swim east until you reach a small island. On the island is a campsite, you'll find the first frog ontop of a crate there.
2. Shore Leave: After fending off the attacks on the stranded VTOL go to the beach and walk along it until you come across a shack. This is the same shack where you find the radio. Outside the shack on the shore is an overturned boat. Hit the boat with your fists to move it because under it is the frog.
3. Adapt or Perish: After losing sight of Lee for the second time, when you come across Koreans fighting a Hunter, go to the right of them and up a small path to a frozen bar you previously went there in Call me Ishmael. In the right bathroom of the bar you will find this frog on the toilet.
4. Frozen Paradise: At the mining facility jump onto the South-West most building. Fall down the south face of this builidng onto a balcony, the frog will be on a weapon crate.
5. Below the Thunder: When you go up the elevator instead of walking out of it jump ontop of it and go through the vents. At the only dead-end of the vent you will see the cloaking frog.
6. From Hell's Heart: After you head through the second tunnel (including the first one) get off the train and the one that has been next to you should stop right outside the tunnel. Get on top of the train and face the tunnel. The frog will be ontop of a ledge above the tunnel. You'll have to do a running strength jump to grab the frog.
7. All the Fury: In the building adjacent and connected to the radio tower, in the kitchen there is three fridges lined up against a wall. Open up the middle one and you will find the frog on the top shelf. In the same building as the radio for this level.