The TEAM Explorer Combat card only affect Explorer Dogs.
The Spanish Conquistadors brought dogs with them to the New World. These were big, fierce dogs, probably a mix of mastiff and greyhound. They were good at tracking, hunting, and killing prey (often human). Becerrillo, which means "little bull calf," was owned by Spanish Conquistador Ponce de Leon. Becerrillo sired the more famous Leoncico, "little lion," who stowed away in a wooden cask with his owner, the Explorer Vasco Nunez de Balboa.
Explorer Dog. Your Explorer's loyal companion.
The Explorer Dog is available to European civilizations other than the Spanish and, like the Explorer, cannot die when its hit points reach 0. Instead, it collapses and must be rescued when an allied unit or building is near and it has enough hit points, or ransomed.
The Explorer Dog is automatically upgraded in every Age up.
The Dog was originally cut from the original Age of Mythology, however it was meant to return as a trainable unit for the Chinese, likely as a scout, before becoming just a Scenario Editor unit, similar to the Cataphract.
Age of Empires III
When the Explorer Dog collapses, a text box appears near it that quotes Hamlet's final line from the Shakespearean play Hamlet: "Horatio, I am dead; Thou livest; report me and my cause aright To the unsatisfied."
Although the War Dog/Explorer Dog unit portrait shows a German Shepherd dog, the two in-game variants resemble an Belgian Shepherd Malinois and a English Mastiff.
Both variations of the Dog in Tale of the Dragon
Variant 1 of the Dog
Variant 2 of the Dog
The two in-game variants of the Explorer Dogs in Age of Empires III