tickle the tank train

tickle cannot be countered Flying Trample

when you cast tickle the tank train tickle the
tank train's base power and toughness become 500/500
{p/b}{p/c}{p/g}{p/r}{p/u}{p/w}{g/u}{10}{x} cerate x times 500
copies of tickle the tank train
tickle the tank train cannot leave the battlefield