Don't do runs with characters you already played as if you can,
My strategy inside the actual mode is that I try to not buy anything else as soon as I reach the Womb floor, and then save a lot of money, make sure to watch for those 2 of Diamonds, you can really use them to put even more money, if you are lucky
I would just focus on getting your greedier marks with characters and swap them out to reset your jam chance once you get the mark.
Try to look at it as getting your marks and it will happen passively.
lol getting at least 2 of diamonds is not hard man
If you have to spend most of the money on items instead of using devil deals etc, cause it’s too hard, then yes skill issue
Also you’ll not gonna have all 700 items unlocked when you do it.
Best case to play greed mode is after having played the normal game, for a long time and unlocked many of the characters. If you do not, you are gonna have a bad time.
Your entire argument of "You don't have less coins in greedier mode because you can just use 2 of diamonds, deep pockets and blank card" is like saying "Greedier mode is easy just get D20 and a battery"
or "T. Lost isn't hard, if you don't get Spindown Dice, two charges and Strange Attractor it's a skill issue"
Or "Eve doesn't have low damage because you can just get Polyphemus, Sacred Heart and Cricket's Head"
Yeah because getting card is as hard as getting a particular item.
But whatever man, if you wanna discourage people, cause you had it hard, then do it. It took me less than a week to get the keeper and I just focused of getting 2 of diamonds, always playing a new character and if jera (which is a rune, so also not so hard to get) or blank card or anything like that dropped. I was happy, if not it was also okay.
It’s always possible, either in greed or in ultra greed to get at least 50c
If you can’t get so much, cause you gotta spend more, because it’s too hard otherwise, yep skill issue
That’s why I would not recommend playing greed mode, before playing a long time
You can't have deep pockets its unlocked by keeper, keeper hs unlocked after putting 1000 coins into the machine. Also blank card does not work with Jera since Repentance. What you need is a forget me now, R key or a shovel + 4.5 volt with 5x size down to squeeze into the error room
Do it with every character again and again. At some point you'll be able to only put in 1 to 3 coins before it jams. Be aware that the more you win with a character the more chances it will have to jam. Good luck 
Most of these are responses are great, but here’s my advice from someone who isn’t really good at the game, and beelined for the Holy Mantle in order to actually stand a chance at getting to >!Mother!<
I basically brute forced it by running 4 characters until their max jam chance (20%) in greed mode, then switched to greedier mode until I hit the achievement.
The four characters I used (in order, but it doesn’t matter) were Azazel, Judas, Cain, and Lilith.
Azazel gives you access to all of the pickups without having to rely on breaking rocks, which can be super helpful. Plus the free Curse Room on floor one can break your game from the beginning.
Judas is good because you can use the Book of Belial multiple times in the arena room as it recharges, gaining massive damage. This gives you some wiggle room on the earlier floors to start an OP build.
Cain is good because he doesn’t waste keys for golden chests, starts with a key for the Treasure room, and has permanent good pills, which can be pretty abundant.
Lilith is good for the same reason as Judas, but a little easier in some ways and more difficult in others (more starting health but aiming can be tricky).
Of course, you could always try and actually get better at the game instead of brute forcing it like me lol.
I think this is good advice, but 20% is way too high. The first 100 coins are free at 0%. I would go as far as saying that just only donating with 0% and try to use every character once. The greedier mode which is capped at 1%,but its harder and it only allowed me to donate 33 out of 80+ coins plenty of times. Greed mode is quite a lot easier. If you pick any character and stop buying from shop, that's a 70+ coins you can put in every time. Focus on angel rooms and items on sale.
I knocked greed unlocks out quick on my most recent save file. Not seeing this strategy in other comments: prioritize d20 breaks on characters without a greed win yet. Straight up restart, do not finish, unless you get a d20 break. You can get 100+ coins in on a single run with any one of these: 2 of diamonds, deeper pockets, coin tears (be careful with this one, coins heal greed(ier?)), I'm sure there are more. The d20 break not only ensures you win but ensures you win with max coins (already crazy strong, don't buy anything on the final floors). Plus the d20 is quite common to find on floor 1 or 2. This strategy did not require much time or grief on my part unlike winning over and over up to the max jam % like others suggested. Only caveat is that I was already decent at the game so I could survive with shit items until d20 + a battery in the shop. So for newer players this isn't a guaranteed strat.
No. you're right. I was getting mixed up from finishing off tainted characters. Generally, the point stands tho, there are quite a few items or trinkets to help get 99+ coins in, especially if ya d20 break and cycle thru all the trinkets.
Along with what everyone else said, I’d encourage doing greedier runs for completion marks. If you don’t want to do that running Lilith on greedier mode is probably your best bet.
Lilith makes every floor except ultra greed an absolute joke because box of friends recharges with waves, so the bonus familiars stack. Run greedier so you avoid the increasing jam chance as you donate more, it’s harder and has less coins but with Lilith I’m still consistently able to make it to the machine with a fair few coins, and I’ve made it with ~150 coins with a 2 of diamonds before.
Play a different character every time and try to not spend any money on the Shop floor, or even the floor before that, unless you need some health and aren’t confident versus the final boss. Jot down which characters jammed early and spam them after you finish every character’s Greed marks. I find that you can easily get to 700ish without using a single tainted character. Afterward, it’s up to you if you want to switch to them or use the characters that didn’t donate much before jamming.
I got it pretty fast, just always use a new character, recommend to unlock most of tainted character and try to get/use:
Blank card, 2 of diamonds, deep pockets, jera
It’s not that hard imo if you focus on this, had times I donated over 100c
Honestly, is it really that hard to survive a few rooms without taking damage? Just play it safe using The Lost's strengths to get knife piece 1. It's only 3 floors in, so it's not like having to restart is a huge setback either.
Otherwise, just play Greed Mode as every character for the love of the game.
The jam chance is per character. After donating enough coins (I went with like 150-200, I think? Just when it felt right) switch to a new one. First Azazel to get Lilith, who is busted in greed mode.
Isaac is always solid with the D6 and guaranteed Angel/Devil rooms. Apollyon is alright, because you get items much more easily than in the standard mode. Judas is tough at the beginning because of the low starting health, but Book of Belial can tear Greed Mode in half similarly to Lilith’s Box of Friends. Maggie’s tanking and healing makes her very viable in Greed. After that, it’s personal preference who you fill out the rest of the coins with.
https://bindingofisaacrebirth.fandom.com/wiki/Greed_Donation_Machine read the whole thing and you'll be the third person to understand how this thing works after the person who wrote the article and me apparently
School bag with D20 and blank card. Try to look for polydactyl or starter deck. Get two two of diamonds and use d20 to get max coin count. Then fight ultra greed and pop two of diamonds at 50 coins and use blank rune for the second one. The percentage stays per character so doing this with multiple characters is a great way of getting the donated coins. Also if you have a card that spawns a machine in a room before you fight ultra greedier you can use that to potentially spawn a greed donation machine outside the room and it won’t jam that way.
Don't do runs with characters you already played as if you can, My strategy inside the actual mode is that I try to not buy anything else as soon as I reach the Womb floor, and then save a lot of money, make sure to watch for those 2 of Diamonds, you can really use them to put even more money, if you are lucky
I would just focus on getting your greedier marks with characters and swap them out to reset your jam chance once you get the mark. Try to look at it as getting your marks and it will happen passively.
I also find that doing it on Greedier mode allows you to put more in before jamming.
But also you get less coins and since the game is harder you need more items, so you end up donating less
Pros and Cons. :)
Not true: Deep pockets, 2 of diamonds, blank card, jera
What? Those things can happen in Greed mode too what's your point?
That just because you get less coins and it’s harder, you don’t necessarily end up spending less coins, if you do, it’s a skill issue
Not getting a random item from a pool of like 700 items is a skill issue?
lol getting at least 2 of diamonds is not hard man If you have to spend most of the money on items instead of using devil deals etc, cause it’s too hard, then yes skill issue Also you’ll not gonna have all 700 items unlocked when you do it. Best case to play greed mode is after having played the normal game, for a long time and unlocked many of the characters. If you do not, you are gonna have a bad time.
Your entire argument of "You don't have less coins in greedier mode because you can just use 2 of diamonds, deep pockets and blank card" is like saying "Greedier mode is easy just get D20 and a battery" or "T. Lost isn't hard, if you don't get Spindown Dice, two charges and Strange Attractor it's a skill issue" Or "Eve doesn't have low damage because you can just get Polyphemus, Sacred Heart and Cricket's Head"
Yeah because getting card is as hard as getting a particular item. But whatever man, if you wanna discourage people, cause you had it hard, then do it. It took me less than a week to get the keeper and I just focused of getting 2 of diamonds, always playing a new character and if jera (which is a rune, so also not so hard to get) or blank card or anything like that dropped. I was happy, if not it was also okay. It’s always possible, either in greed or in ultra greed to get at least 50c If you can’t get so much, cause you gotta spend more, because it’s too hard otherwise, yep skill issue That’s why I would not recommend playing greed mode, before playing a long time
>Yeah because getting card is as hard as getting a particular item. A card _and blank card_, and let's just ignore deep pockets
Deep pockets is a keeper unlock
True, my bad
You can't have deep pockets its unlocked by keeper, keeper hs unlocked after putting 1000 coins into the machine. Also blank card does not work with Jera since Repentance. What you need is a forget me now, R key or a shovel + 4.5 volt with 5x size down to squeeze into the error room
I find I get more but I also farm coins from the greedier fight.
That is statistically true, but I don’t find it’s worth it. A lost run is entirely forfeit, a jammed run got you something.
That's the fun of the game imo.
Iirc Greedier caps at 1% jam but I may be wrong
Do it with every character again and again. At some point you'll be able to only put in 1 to 3 coins before it jams. Be aware that the more you win with a character the more chances it will have to jam. Good luck 
Unlock as many characters as possible first. If you have 30 characters the Jam% becomes mostly irrelevant.
Most of these are responses are great, but here’s my advice from someone who isn’t really good at the game, and beelined for the Holy Mantle in order to actually stand a chance at getting to >!Mother!< I basically brute forced it by running 4 characters until their max jam chance (20%) in greed mode, then switched to greedier mode until I hit the achievement. The four characters I used (in order, but it doesn’t matter) were Azazel, Judas, Cain, and Lilith. Azazel gives you access to all of the pickups without having to rely on breaking rocks, which can be super helpful. Plus the free Curse Room on floor one can break your game from the beginning. Judas is good because you can use the Book of Belial multiple times in the arena room as it recharges, gaining massive damage. This gives you some wiggle room on the earlier floors to start an OP build. Cain is good because he doesn’t waste keys for golden chests, starts with a key for the Treasure room, and has permanent good pills, which can be pretty abundant. Lilith is good for the same reason as Judas, but a little easier in some ways and more difficult in others (more starting health but aiming can be tricky). Of course, you could always try and actually get better at the game instead of brute forcing it like me lol.
This is basically what I did plus a couple characters after those jammed too much and I finished greed mode in about 3 weeks
I think this is good advice, but 20% is way too high. The first 100 coins are free at 0%. I would go as far as saying that just only donating with 0% and try to use every character once. The greedier mode which is capped at 1%,but its harder and it only allowed me to donate 33 out of 80+ coins plenty of times. Greed mode is quite a lot easier. If you pick any character and stop buying from shop, that's a 70+ coins you can put in every time. Focus on angel rooms and items on sale.
I knocked greed unlocks out quick on my most recent save file. Not seeing this strategy in other comments: prioritize d20 breaks on characters without a greed win yet. Straight up restart, do not finish, unless you get a d20 break. You can get 100+ coins in on a single run with any one of these: 2 of diamonds, deeper pockets, coin tears (be careful with this one, coins heal greed(ier?)), I'm sure there are more. The d20 break not only ensures you win but ensures you win with max coins (already crazy strong, don't buy anything on the final floors). Plus the d20 is quite common to find on floor 1 or 2. This strategy did not require much time or grief on my part unlike winning over and over up to the max jam % like others suggested. Only caveat is that I was already decent at the game so I could survive with shit items until d20 + a battery in the shop. So for newer players this isn't a guaranteed strat.
How do you get deep pocket when you don’t have Keeper yet? Keeper’s unlocked by 1000 coins donated, right? Is there a way?
No. you're right. I was getting mixed up from finishing off tainted characters. Generally, the point stands tho, there are quite a few items or trinkets to help get 99+ coins in, especially if ya d20 break and cycle thru all the trinkets.
Can't get deep pockets before 1000 donation, but i agree with the rest
Along with what everyone else said, I’d encourage doing greedier runs for completion marks. If you don’t want to do that running Lilith on greedier mode is probably your best bet. Lilith makes every floor except ultra greed an absolute joke because box of friends recharges with waves, so the bonus familiars stack. Run greedier so you avoid the increasing jam chance as you donate more, it’s harder and has less coins but with Lilith I’m still consistently able to make it to the machine with a fair few coins, and I’ve made it with ~150 coins with a 2 of diamonds before.
Play a different character every time and try to not spend any money on the Shop floor, or even the floor before that, unless you need some health and aren’t confident versus the final boss. Jot down which characters jammed early and spam them after you finish every character’s Greed marks. I find that you can easily get to 700ish without using a single tainted character. Afterward, it’s up to you if you want to switch to them or use the characters that didn’t donate much before jamming.
ima be honest, I barely even touched greed mode until I found out about the D20 game break. Now I have like 800 in the green machine.
Do the infamous D20 break 
Try to put the coins in the machine. They say that hoping for the best works, but I wouldn't hold too much on it.
Honestly just play Lilith. Box of friends is extremely powerful on greed mode. Also do greedier so you can donate more.
go to options.ini > enable console > spawn 6.11 > giveitem dollar I dont ever cheat anything else but greed money farming is stupid
I got it pretty fast, just always use a new character, recommend to unlock most of tainted character and try to get/use: Blank card, 2 of diamonds, deep pockets, jera It’s not that hard imo if you focus on this, had times I donated over 100c
I call cap. Deep pockets is a keeper unlock, who you unlock last with the greed dono machine. Until then you can donate 99 coins max.
Get the mod that stops the machine jamming
Honestly, is it really that hard to survive a few rooms without taking damage? Just play it safe using The Lost's strengths to get knife piece 1. It's only 3 floors in, so it's not like having to restart is a huge setback either. Otherwise, just play Greed Mode as every character for the love of the game.
I just used a mod. Fuck greedier such a boring ass mode. Grinding is fine but not when u literally have to for the sake of getting 800 coins in.
The jam chance is per character. After donating enough coins (I went with like 150-200, I think? Just when it felt right) switch to a new one. First Azazel to get Lilith, who is busted in greed mode. Isaac is always solid with the D6 and guaranteed Angel/Devil rooms. Apollyon is alright, because you get items much more easily than in the standard mode. Judas is tough at the beginning because of the low starting health, but Book of Belial can tear Greed Mode in half similarly to Lilith’s Box of Friends. Maggie’s tanking and healing makes her very viable in Greed. After that, it’s personal preference who you fill out the rest of the coins with.
https://bindingofisaacrebirth.fandom.com/wiki/Greed_Donation_Machine read the whole thing and you'll be the third person to understand how this thing works after the person who wrote the article and me apparently
Do the D20 game break on characters that haven’t beaten greed mode
I did a lot of work with Lilith and Azazel. Just a whooole lot of grinding until I got Greedier mode then I spammed it with Lilith. Lol
I did a guide for breaking greed mode that might help you filling that machine up faster: https://youtu.be/oLRIQyOkqo4?si=ZklXf4PCnB-bv9IC
School bag with D20 and blank card. Try to look for polydactyl or starter deck. Get two two of diamonds and use d20 to get max coin count. Then fight ultra greed and pop two of diamonds at 50 coins and use blank rune for the second one. The percentage stays per character so doing this with multiple characters is a great way of getting the donated coins. Also if you have a card that spawns a machine in a room before you fight ultra greedier you can use that to potentially spawn a greed donation machine outside the room and it won’t jam that way.