Having Issues with GUN-D4M (Hard Difficulty)

[Varying Chimera]

I'm doing this solo right now. I recently had to re-do the rest of the entire fortress (hard drive suddenly went bad when I went to defeat the Autumn and Summer Elder Fae duo, hadn't saved at all between then and the beginning of Pumpkin Woods), and the GUN-D4M boss is the only part I'm having a hard time with. During the Last Stand, I always die when there's about 4 or 5 seconds remaining on the clock somehow. Any tips would be helpful.

Current Setup:
Equipment
-Weapon: The Stinger / Apprentice Rod
-Shield: Crystal Shield
-Armor: Green Slime Armor
-Hat: Big Fish
-Accessories: Red Ring + Rabbit's Foot
-Shoes: Rollerblades
-Facegear: Blindfold

Skills
-Spirit Slash (Lvl 8)
-Frosty Friend (Lvl 5)
-Static Touch (Lvl 3)
-Protect (Lvl 1)

Talents
-Surgeon (Lvl 1)
-Last Stand (Lvl 3)
-Strength (Lvl 5)
-Last Breath (Lvl 3)
-Second Wind (Lvl 3)


I equip the Apprentice Rod before Silver Charging Frosty Friend and Bronze Charging Static Touch (since I'm not sure if there's any difference when I switch to a different weapon after both spells have already been casted), then switch to the Stinger before starting the fight. I go ham on the hands immediately, since the first round is easy to avoid damage. I take out 1/3 of the boss' health bar if I go for safety, roughly an entire 1/2 if I let myself take the 40 from the body's electricity.
I'll use Protect when able to, along with a Defense potion if I remembered to grab one before the fight. But no matter what I do exactly, I'll get rid of GUN-D4M's entire health bar while leaving myself at about 1/2-3/4 max health, then die due to his Last Stand.

 

[Own]

Your save file that you lost is likely backed up here, along with their world file. C:\Users\Arc\AppData\Roaming\Secrets of Grindea

If you want tips, use two red rings and a Phaseman Helm. Also buy attack and defense potions. ATK when you're fighting, DEF when he uses a barrage superattack. Also use an iron shield. Or a barrel shield, if you can find one from a barrel.

 

[Varying Chimera]

Your save file that you lost is likely backed up here, along with their world file. C:\Users\Arc\AppData\Roaming\Secrets of Grindea

If you want tips, use two red rings and a Phaseman Helm. Also buy attack and defense potions. ATK when you're fighting, DEF when he uses a barrage superattack. Also use an iron shield. Or a barrel shield, if you can find one from a barrel.

Pretty sure that would've disappeared when the hard drive went bad. Recently installed a brand new one, but thank god Steam has cloud saving.

Gonna be fun trying to get that Phaseman Helm... Thanks for the tips. I took a quick look at some of the crafting things and there's something that's slightly better than the iron shield that I could get at this point, but it's a pain in the ass to grind Wisps. Not sure about the barrel shield though.

 

[tkld178]

You can get the barrel shield from destroying barrels at a very low chance. The red ring you can buy from the accessory merchant in town.

This is cheesy but if you have defensive gear you can switch to it in menus from your offensive gear. Another thing to look into is the first big attack he does happens at a certain health% so if you can get him above it on the first attack phase maybe with some extra damage you can finish him without having to deal with the middle bullet hell phase.

There are a few more pieces of gear you can get that will help. You can get an attack increase helm from getting lucky from pumpkins or you can buy one from the hat shop(one at hat shop has 10 less attack). I would personally go with the spectacles(from hat shop) for the magic increase for your summon and your static touch. Another thing is you can also switch your body to one of the robes that gives magic since you won't need to worry about damage during that phase. Barrel shield will be an improvement over your current shield, but most would for that fight. Crystal shield is a weak shield that is only good at taking perfect blocks, which you should not be going for much in this fight.

One strategy I like during the last stand is to always have your shield up. It is easier to control your character at that speed than normal running with you have to go through very small spaces. I would also unsummon your FF because he does not help for this and can even distract you.

 

[Varying Chimera]

You can get the barrel shield from destroying barrels at a very low chance. The red ring you can buy from the accessory merchant in town.

This is cheesy but if you have defensive gear you can switch to it in menus from your offensive gear. Another thing to look into is the first big attack he does happens at a certain health% so if you can get him above it on the first attack phase maybe with some extra damage you can finish him without having to deal with the middle bullet hell phase.

There are a few more pieces of gear you can get that will help. You can get an attack increase helm from getting lucky from pumpkins or you can buy one from the hat shop(one at hat shop has 10 less attack). I would personally go with the spectacles(from hat shop) for the magic increase for your summon and your static touch. Another thing is you can also switch your body to one of the robes that gives magic since you won't need to worry about damage during that phase. Barrel shield will be an improvement over your current shield, but most would for that fight. Crystal shield is a weak shield that is only good at taking perfect blocks, which you should not be going for much in this fight.

One strategy I like during the last stand is to always have your shield up. It is easier to control your character at that speed than normal running with you have to go through very small spaces. I would also unsummon your FF because he does not help for this and can even distract you.

I managed to grab the Phaseman's helmet more easily than expected. Picked up the iron shield because I wasn't sure how good the barrel shield was, and I felt too lazy to look up the info on it.

The attack potions that @Own recommended worked a bit better than expected, so I went with those as well. My FF was actually able to block at least a few hits during the Last Stand which helped me out, and typically my shield gets broken at some point during the Last Stand which makes it harder on me, though charging a skill seems to make me move almost as slowly as I would with a shield up.

 

[Catu]

DEF pots!!! Grab more than one make sure they are up! Do this on the last stand.

 

[Varying Chimera]

DEF pots!!! Grab more than one make sure they are up! Do this on the last stand.

I grabbed 6 of both Damage and Defense. It seems like they gave me a confidence boost more than a defense boost, because I still had somewhere over 225 HP out of about 350 left over after the Last Stand.
I think I probably would've had about 150 or less if I didn't have the confidence boost, but whatever.

Thanks for the help, guys!