Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
you may be asking yourself if you should choose Tryndamere as a character to buy.
He annoys the enemy to hell when built right and use him right. I would suggest playing practice games with him until you get his mechanics down, and remember, he can spin through walls.
This is my build that I worked out slowly. I find that it has very good survivability and damage. end game crits are around 1.5k if you get all of the items. high attack speed and high crits. then the life steal keeps you up when you have to run or when you're in a 1v1 fight.