Always build according to the enemy team and who you're versing. you can replace any of the items from the "Standard Build" except for Triforce. Imo Triforce is what makes Irelia viable as a champion, so always buy it and always rush it.

- Tank Items: After Triforce just build whatever tank items are best.

- Damage Items: Only build BORK if they have multiple tanks or if you are fed and well farmed. Buy Sterak's Gage if they have bursty champions, like most mages and adc's, I really like this item. Buy wit's end if they have a triple ap comp (and you're vsing magic damage), bypass the Trinity Force taboo and rush Wits End first item (build Triforce second). Buy youmuus only if you're ahead, and if you're vsing someone you want to burst down quickly like riven, tbh it's more of a troll item but it's really fun to use correctly.

- My Standard Build
The cdr from Frozen Heart and Spirit Visage allows you to use your ult to clear big waves late game and have it up soon enough for team fights. The mana from Frozen Heart stops you from going oom when q spamming to clear waves.