Input the below seed into the community challenge page.
Take the Wrathful option for your champion and then after beating the first room take the Sharpen card (4 damage and 4 spikes)
The idea is to stack spikes on your champion and make sure he is in front on the first floor. He is the only monster you really need so don't worry about picking up any others. You can put the Stewards on floors 2 and 3 to mop up anything that gets by at first but after your champion has enough spikes he pretty much destroys everything .
I took the upgrade magic path first to reduce my Sharpen to 1 ember then added holdover so I always have it once cast. Make sure you don't use any spells to kill monsters on the first floor. You need them to both hit and die to your champion.
After you beat the first boss, take the right path with the random artifact option. Get Grrg's Goad which will give your champion an additional stack of multistrike.
Lastly, at the trinket shop before the last boss, reroll once and buy the Railhammer which gives +4 armor whenever armor is put on a friendly
This will unlock the Win at Covenant 5, 10, 15 and 25 achievements as well as the Win with all covenants enabled on The Hellhorned achievement.