Most monsters cant knock out Dragonite in one turn, so you get to deal as much damage as possible in two turns
Using extra rules text to add behold to the existing champion mechanic proved unwieldy (and worked differently than champion because the creature returns to your hand)
The limited availability enhances its allure, inviting collectors to cherish not just Squirtle's charm but also the unique narrative woven into this rare piece of Pokmon history
Casualties of War, In Garruk's Wake blow up anything that stands in your way
For context, Mega Charizard Y ex's attack is powerful enough to wipe out almost every card in the game for the small sacrifice of 50 HP, and the only cards truly capable of countering the fiery icon are from the same new set
In general, I would look at these two factors when looking to include cards not of your tribe's creature type: Is this creature so strong that it, on its own, is generally stronger than my tribal creatures when they are receiving bonuses and/or empowering my other cards