"It spits fire that is hot enough to melt boulders" (Pokémon Red/Blue Pokédex entry)
On average, the temperature it would take to melt stone into magma would be between about 1300º - 2400º Fahrenheit (700º - 1300º Celsius). At about this temperature, the human body in its entirety would melt as well.
"It is said to live 10,000 years" (Pokémon Diamon/Pearl/Platinum Pokédex entry)
Approximately 10,000 years ago, the Ice Age ended, agriculture was first becoming widespread, and the first human settlements were being built. A Wartortle alive today could have been alive since prehistoric times.
"This Pokémon flies at Mach 2 speed, seeking prey." (Pokémon Yellow Pokédex entry)
Mach 2 is twice the speed of sound, which normally equates to approximately 1500 miles per hour (approx. 2500 kmph), or about 1150 feet per second (350 meters per second), the speed at which many bullets travel. Planes traveling at these supersonic speeds are made of special metals that won't melt at this speed.
"Gnaws on anything with its tough fangs. It can even topple concrete buildings by gnawning on them." (Pokémon Gold Pokédex entry)
Normal concrete has the strength to withstand up to 10,000 psi (pounds per square inch) of pressure. The living animal with the strongest bite force is the crocodile, with a bite that can exert approximately 5,000 psi of pressure. Raticate would need to have a bite at least twice as strong as that, considering.
"Arcanine is known for its high speed, It is said to be capable of running over 6,200 miles in a single day and night." (Pokémon Ruby/Sapphire Pokédex entry)
This would mean Arcanine would need to run about 260 miles per hour (418 kmph), or about 380 feet per second (116 meters per second), for 24 hours straight. 6200 miles is longer than the distance from L.A. to Moscow.
"It's four ruggedly developed arms can launch a flurry of 1,000 punches in just two seconds." (Pokémon FireRed Pokédex entry)
Assuming Machamp is using all four of its hands, this would mean 250 punches in two seconds, 125 punches in one second, or one punch every 0.008 second. Machamp could perform 37-and-a-half punches with one arm in the time it takes a person to blink an eye.
"It throws punches that are faster than a bullet train." (Pokémon FireRed Pokédex entry)
Most bullet trains run an average speed of about 300 kilometers per hour (about 186 mph). Taking Hitmonlee's size into consideration, this means it could probably throw a single punch in about 0.0085 seconds. The worlds record for human punching measured about one punch in 0.0745 seconds, almost nine times slower than that.
"It can spend all day in water, since it can inhale and store a lager volume of air." (Pokémon Platinum Pokédex entry)
The sperm whale can hold it's breath for two hours, longer than any other mammal alive. The saltwater crocodile can hold it's breath for up to three hours, longer than any animal with lungs. Azumarill can hold it's breath eight times of a crocodile, and twelve times that of a sperm whale.
"Magcargo's body temperature is approximately 18,000º Fahrenheit." (Pokémon Sapphire Pokédex entry)
The surface of the sun is about 9980º Fahrenheit (5526º Celsius). That would make Magcargo's body temperature about 1,8 times as hot as the surface of the sun.
"It feeds on soil. After it has eaten a large mountain, it will fall asleep so it can grow." (Pokémon Gold Pokédex entry)
Theoretically the amount of dirt it would take to equal the size of a large mountain about 20,000ft (6096 meters) tall could require as much as 4,410,000,000 pounds (2,000,000,000 kg), or 2,205,000 short tons of dirt. The world's largest mountain, Mt. Everest is about 29,029 feet (8,848 meters) tall, and would have a volume more than twice that amount.
"Blaziken has incredible strong legs - it can easily clear a 30-story building in one leap." (Pokémon Sapphire Pokédex entry)
On average, a single story is between 10-13 feet (3-4 meters) tall. That would mean Blaziken could make a vertical leap of over 300-390 feet (90-120 meters). That's more than sixty times it's height.
"It's cries equal a jet plane in volume." (Pokémon Emerald Pokédex entry)
Hearing can be damaged by sustained exposure to 90dB (decibel) sounds (about as loud as heavy traffic). At 125dB, pain is felt (about as loud as a pneumatic drill). At 140dB, permanent hearing damage can occur even with short term exposure. At 180dB, complete death of hearing tissue occurs. The sound of a jet engine measures about 140dB from 100 meters (about 328 feet). At close range with no protection, it could burst the eardrums.
"by inhaling to its maximum capacity, a Wailord can dive close to 10,000 feet beneath the waves." (Pokémon Emerald Pokédex entry)
10,000 feet (about 3048 meters) underwater, there would be more than two tons of water pressure on top of you, equal to more than 300 atmospheres of pressure. The temperature that far down usually ranges from 30-39º Fahrenheit (3-4º Celsius), and there is almost no light. The sperm whale, which can dive deeper than any other whale, can barely get close to this depth. However, a sperm whale weighs as much as 45 short tons (41,000 kg) on average, while Wailord weighs 877,4 pounds (398 kg).
"It is said that a home visited by Snorunt will prosper. It can withstand cold of minus 150º Fahrenheit." (Pokémon FireRed/LeafGreen Pokédex entry)
The lowest temperature ever recorded on Earth was -128º Fahrenheit (-89º Celsius). The human body at it's absolute best can't survive long past -40º Fahrenheit (-40º Celsius) external temperature, when the moisture in the lungs begin to freeze
"It sprays a vile-smelling fluid from the tip of its tail to attack. Its range is over 160 feet." (Pokémon Diamond Pokédex entry)
A real skunk can spray it's fluid with accuracy up to 16 feet (5 meters). Skuntank can launch the fluid ten times this distance. 160 feet is the width of a regulation football field.
Conclusion: Pokémon are really freaking hax