Monster Train

Input the below seed into the community challenge page.

BandsLiteracyMaker

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.

Turn on the trial for the level 4 fight to gain the Resonant Shard artifact which gives an additional +1 attack per stack of rage.

Take the right path on level 7 to grab the Gnarled Root artifact from the shop which gives +1 attack per stack of spikes.

Lastly, at the trinket shop before the last boss, pick up the Petrified Crucible which deals +1 damage per stack of spike then 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.

Enjoy!

For anyone who is looking for an updated seed, you can use ResortToughOverseas. Unlocked as of 8/18/2021.

I also uncovered "It's a Secret" - Find a rare flower for 15G. The Remains of Armageddon event popped on floor 3 in the concealed caverns. You simple select 1 of the 3 cards offered and do not play it. The train will stop just after defeating a boss and an artifact is given to you, which unlocks the achievement.