I this is my first build on mobafire and englis is not my home language so no complaining about the grammar please. I'm guilletui a silver five (now) in league of legends and also member of theQC master. Tryndamere is my favourite champion in the league for now because his kit is just amazing. if you want to use the destroyer build, you need to be good with him, if you are not use my jungle build or his normal build.

pros
-high burst damage
-invincible with his ult
-assassin like fighter
-almost alway's win trade when he got his statikk shiv
-super slow/damage reduction
-good sustain with bloodlust
-he is tryndamere
cons
-very squishy during laning phase
-item reliant
-hard to pop ultimate

for runes take AD marks armor seals scaling MR glyphs/crit chance glyphs and critical damage quint/life steal quint.

-AD mark will help you farm in the first 10 minutes and help you doing more damage late game.

-armor seal are pretty much basic rune with any champion. they will help you survive to poking in the first 15 minutes.

-the scaling magic resist glyph are basic as the armor seal. all AP champion does less damage in the first 20 minutes and they do more damage each time they level up and buy big AP item such as rabadons cap./the crit chance glyphs are usefull during the laning phase until you get your infinity edge.

-the crit damage quint are so usefull on him that they were made for him. He does most of his damage with crit strike so more damage output=more chance to kill someone./the life steal quint are usefull if you need practice with him or if you are jungling.