Solution taken from Clement_RKG on Steam:
https://steamcommunity.com/sharedfiles/filedetails/?id=32164...To create the 1000+ value coin, you will have to use the small pink enemy to your advantage : it can eat coins and will grow larger and larger until you kill it.
Having 'Wealth' upgrades can help in accumulating coins. Additionally, they advise you to avoid 'piercing' upgrades when using 'epsilon' since you do not want to accidentally kill the enemy. If it becomes stationary, use the window border to push it into the coins.
You should also note that if you don't want to go through the process they described, you can also survive for about 30 minutes. That way, you won't need to worry about feeding monsters; there will be plenty of big coins without you actually doing something (assuming you bought some 'wealth' upgrades during the game).