Army of Ruin

These achievements for completing stages without moving will seem impossible at first, and that's because they are. The following things are virtually mandatory unlocks to be able to survive these stages without moving:
 

• Unlock Selina as a character. She has a skill that lets her heal most of her health, which is crucial since you can't rely on random food drops. Also, her passive skill does Thorns damage to enemies that touch you, which is another crucial thing for bosses (and avoids the need for the Thorns trinket). Selina is unlocked by defeating all optional bosses with Ariana on Graveyard II - Ruin I
• Upgrade Experience and Pickup to at least level 5, but obviously 10 is ideal
• Upgrade Damage to 10
• Upgrade Projectiles at least once. Twice is ideal, but I only had one for all of these challenges
• Unlock the Soul Container (see Soul Container (5G)). This is essentially mandatory for the final boss of each challenge. There's no way you'll kill them before they kill you, so you'll need extra lives
• Unlock Favorites (see Favorites (10G)) and preferably have two bought. This isn't required but it saves you from RNG. You should mark Toxic Stench or Wolf's Fang as a favorite, and then definitely Soul Container for the extra lives you'll need

The goal in this run is to kill all enemies close to you so their gems drop close enough to suck them up without moving. Any weapons that kill distant enemies are a waste and should be avoided. Similarly, knockback should be avoided for the same reason.

The idea with bosses and why we're playing as Selina is that you want them to reach you, stand on top of you, and die from your Thorns damage so that they drop their chest right on you to pick up. Otherwise, since you can't move you wouldn't get any chests. When a boss stands on top of you, watch your health and be ready to press  to use your skill to refill it. With regular bosses, your skill should heal you enough that you can kill them without dying. For the final boss, this won't be enough. You'll need extra lives from the Soul Container. For the first two challenges, I got by with one extra life, but for the Shrine no-moving challenge, I needed four lives to finally kill the final boss, so be prepared for that. 

Another thing I recommend doing is that, if you have six weapons and trinkets unlocked for capacity, downgrade your weapons to five or even four. This is because you won't be leveling up a whole lot doing these challenges, and it's better to have less weapons that are stronger rather than more weak weapons. Your levels will be spread too thin. Invest that money in rerolls to help with RNG. 

Here are the weapons you want to go for:
 

• Necromancer Gauntlets (you'll start with these as Selina)
• Wolf's Fang
• Toxic Stench
• Volcanic Orbs
• Mighty Punch
• Sparksword
• Magatama (lowest priority because it's decently far away from you

As for trinkets, these are the ideal ones (considering you won't be leveling up much or evolving any weapons):
 

• Soul Container (highest priority; should be a Favorite)
• Heavy Greaves/Leather Bracer (high priority)
• Wristband of Grudge (high priority)
• Dragon's Heart/Obsidian Crown/Magic Needle/Sacred Effigy
• Magical Harp/Forbidden Cross + Magnifier (only get Magnifier if you have Harp or Cross to extend pickup range

You're going to be getting hit a lot, so Wristband of Grudge is extremely helpful for tacking on huge damage boosts each time you get hit. Having your Fire Rate up in Upgrades, plus Heaves Greaves and/or Leather Bracers means you'll be firing off with your Gauntlets and Wolf's Fang very often. Just make sure you get Soul Container and get a few points into it before the final boss so you have a shot at surviving.