People tend to forget the main role of a tank in a co-op based game, especially when suggesting it into games such as these where there are no "auto-attacks" and no "100% accuracy" attacks, where damage is avoided with skill, not with
superior arbitrary numbers. This isn't a game where you just line up your four characters with the assigned "tank" sitting closest to the enemy so by nature he's going to be the first they hit, whenever they attack. This is a game where players move around, and monsters attack and miss a lot.
I'm bringing over my experience from Spiral Knights (in relation to Arcade mode) since it seems like the focus of game design is almost identical. There is no "tank" build. (And there is no healing) There is some armor that allows you to soak up more damage, but equipping it means you aren't getting the massive attack (we're talking 30% damage increase and/or 50% faster charging, depending on the equipment) bonus from wearing other armor so it's basically nonviable.
http://forums.spiralknights.com/en/node/109545
However, particular weapons (such the Haze Bombs, specifically designed for inflicting various debuffs to enemies over a large area, but they do no upfront damage) due to how they function (attempting to apply the debuff to all enemies in its radius once every half-second) tend to aggro everything in their radius
very quickly and maintain aggro for a decent amount of time. This is what a tank's role is.
The
main purpose of a tank is
not to take damage. The main purpose of a tank is to prevent the party members from taking damage.
http://tvtropes.org/pmwiki/pmwiki.php/Main/AnAdventurerIsYou
See if you can guess which sort of tank best suits the game mechanics of Secrets of Grindea (without breaking Arcade mode balance)