what axe is suitable?

[Garlyle]

I'm going to disagree with some people in this thread about starting and getting a relic weapon. At this stage of the game, your best bet would be to save up some money (start crafting and sell low level crafting items if you have to) enough to buy the 110 wootz axe. Even normal quality would be perfectly fine. This will give you a huge leg up into starting to tank end game.

Except that's a lot of money. One million+ gil is not a quick achievement, especially if you're fresh to fifty.

Anyway, for Castrum and Praetorium, really any axe that's decently levelled (around level 45-50) will work. Keep in mind they were designed to be done by players who had only just hit level 50, so it's not like you'll be expected to have a level 60 axe or anything.

That said, getting a high item level axe soon is a good idea for aggro reasons; otherwise, be ready for many non-tanks to steal aggro and tank just fine in early level 50 content. There's no way you'll be able to hold aggro against a skilled and geared DPS when you've only got an i45-i70 weapon, although at this point those DPS are also going to be geared well enough to tank just fine if need be.

Finally, I second the motion to grab your Berserker's Bardiche - once you complete Praetorium you can start the relic quest, which will turn that into an i80 weapon for you that's super easily enhanceable to i90 shortly after and will carry you through the majority of level 50 content.