Huntress's Buckler

This only makes sense on a summoner who actually deploys sentries. The extra sentry slot is a flat increase in how much stationary damage you can park around an arena, and the summon damage rides along on your minions too. On a build with no sentries at all it is close to dead weight in an accessory slot you need.

It does not stack with the other Old One's Army accessories. Wearing this alongside the Squire, Apprentice or Monk pieces gives you one copy of the bonus, not several, so pick whichever secondary effect fits your build and fill the other slots with something different.

Despite the name and the slot, it gives no defense at all and it will not combine with Brand of the Inferno for active blocking. If you were planning a melee hybrid built around the block mechanic, this is the wrong shield to build it on.

Ogres are the tier two miniboss of the event, and your odds there are meaningfully better than in tier three. If the buckler is what you want, run tier two over and over rather than pushing into the harder tier and hoping.