The Binding of Isaac is a game I never got into. It had always been on my radar, many of my close friends got really into it over the years, the theming is interesting, and the lategame looks like a lot of fun. However, whenever I sat down to give it another go, I couldn’t help but bounce off of it. The controls felt stiff, a lot of the enemies felt aggravating, progression felt arduous. Skill issue, I guess.

Gif source: https://tenor.com/view/the-binding-of-isaac-cry-about-it-isaac-tboi-repentance-gif-23806995

However, one aspect of the game I always found intriguing when watching friends play was the ways they could manipulate the game into giving them more powerful or useful items. They would scramble the contents of chests, rooms, even influence the layouts of floors in order to ensure they get items that allow them to effortlessly blast through enemies. I was never able to do this; due to both a lack of game knowledge and a lack of necessary unlocks I was more or less stuck with whatever the game gave me. 

Still, I always found this kind of thing compelling. Compared to the game just throwing items at the player, this “luck manipulation” as I’ve started calling it makes the player more of an active agent, as well as making them feel pretty clever at times. These have particularly become a staple in recent roguelike games, where knowing how to swing the odds in your favor is often what separates the newbies from more skilled players.

Perhaps the simplest example of luck manipulation is allowing the player to directly fudge the numbers in their favor, increasing the chances that a favorable outcome is randomly selected. One example of this is dungeon crawlers that allow players to increase their chance of looting rare items from enemies, usually by carrying the right equipment. In Diablo 2 for example, players can insert precious topazes into certain equipment in order to cause dropped items to more frequently possess magical properties.

However, my personal favorite method of introducing luck manipulation is the classic reroll, taking an unfavorable random result and re-rolling it, hoping that the new result will be better. This always comes with some limitation: only being to reroll a given outcome once, only being able to reroll every so often, having a limited amount of rerolls per game, or requiring the player to spend some resource to reroll.

I’m particularly fond of this method because it gives a significant amount of control back to the player, while still retaining a lot of the unpredictability and surprise that comes with RNG. Each decision to reroll is itself a gamble, a calculated one. The player must weigh the potential gain of rerolling an unwanted item with the loss of being stuck with a worse one, or against the cost of performing the reroll itself.

It’s also worth mentioning the choose-one system, where the game draws some choices from a pool (usually 3-5) and allows the player to choose one. This mechanic is in some ways analogous to the reroll: in both cases the player is given the same amount of “stuff” as if they had just been handed a random result, but are given limited control over what exactly that result is by allowing them to discard bad results in favor of better ones. 

While both have their place, I must admit that I typically prefer rerolls. It doesn’t give as much control as the choose-one, but I honestly view that as a plus, as part of what makes luck manipulation so engaging is that it preserves the spontaneity of randomness while giving the player control, and this becomes a lot less present with the choose-one method. Further, allowing a player to simply choose the best of several options lacks a lot of the strategy and risk that comes with rerolls. There’s no weighing of potential gain and loss, no tension from the possibility of a bad call.

Gif Source: https://tenor.com/view/vampire-survivors-gif-24620607

I’d point to Vampire survivors as a cautionary example of what happens when you introduce too much luck manipulation into a game, giving the players too much control over randomness. When first playing vampire survivors, the player is offered three upgrades to choose from each time they gain a level. Occasionally the player gets stuck with an unwanted item in their kit, but the mechanic typically ensures a good amount of player control over their build while still ensuring a level of spontaneity in order to keep runs varied and interesting.

However, by the time the player is halfway through the metaprogression, the player is so bogged down in additional rerolls and item bans that they have near perfect control over their builds, leading to extremely samey runs after a certain point.

This screenshot is from a fairly early game save.

Luck manipulation is a system that walks the line between two opposing forces, player control and randomness. If implemented carefully, it can strike a balance between the two that can bring out the strengths of both. However, this is still a balancing act as we’ve seen with Vampire Survivors. When trying to bridge a gap between two opposing forces, it’s important not to overindulge in either direction, or you’ll produce gameplay that feels unsatisfying.

All unattributed gifs/images were recorded by either me or my girlfriend.