The idea of tank Diana is to take advantage of Diana's engage and passive to its full capacity. WIth your standard full AP assassin Diana build, you dash into the enemy team, press R, and hope the entire enemy team dissapears in front of your eyes. But what happens if someone survives? the squishy Diana that just jumped into the entire team is the one that dissapears instead, and you become reliant on your team having followed up on your engage.

Don't get me wrong, full AP diana is great against very squishy comps, and is overall a more reliant build. But when the enemy team is a bit more tanky, going tanky yourself allows you to fight those who you were not able to one-shot with the standard build.

This build is best into bruisers and tanks, with the idea of DPS-ing them down instead of bursting them (Keep in mind at 3 items you can still one-shot or almost one-shot a squishy with Challenging Smite -> Q -> E -> R

There is a more popuar Tank Diana build going around which has its core build as Sunfire Aegis into Nashor's Tooth. This build is perfectly acceptable, however after testing both my build and the Sunfire Aegis build, as well as multiple variations of the two builds, I have determined this version to be superior once you get to 2 items. The combo of Iceborn Gauntlet into Fimbulwinteris just so strong, and the shielding between Diana W, Fimbulwinter Passive, Shield Bash, and Revitalize makes Diana an unkillable tank.

Plus Diana getting bonus size is kinda funny