To earn this achievement you will need to make use of Mutators. You can access these modifiers via New Run from the main menu, then, it will be located above the Depart button. I noticed them being available after completing my first run, though they may be there on defeat of first run also.
The Mutator you will NEED to use is named: "Fallen Champion"
You can equip 3 mutators maximum so with that in mind, I highly recommend taking "Fast Draw" as this will give all friendly minions Quick (first strike.) "Mansion" (+2 floor limit, this applies to all floors) would be another solid choice. Ultimately the 2 extra mutators are your choice to make to best fit the clans you are running with.
Should you go with Fast Draw & Mansion:
All I did was take the highest attack minions offered to me and trait stones basically fit wherever needed. [Any +Attack & Multi-strike.] Try to build up gold as best you can and always head to the Merchant of Steel if possible. Run was done with Hellhorn & Awoken. May as well go for this on Ascension 0.