Decoding The Binding of Isaac Completion Marks: A Comprehensive Guide

The Binding of Isaac, a roguelike shooter with layers of complexity, thrives on its replayability and the sense of accomplishment tied to conquering its many challenges. Central to this feeling of achievement are the completion marks, visual indicators on each character’s post-it note that showcase which bosses and challenges you’ve overcome. Understanding these completion marks is crucial for progressing in the game and unlocking its vast secrets. This guide provides a comprehensive breakdown of what these marks represent and how to obtain them, offering insights for both newcomers and seasoned players alike. Knowing what each completion mark means will significantly enhance your gameplay experience.

Understanding the Completion Marks

Each character in The Binding of Isaac has a post-it note associated with them on the character selection screen. This post-it note tracks your progress by displaying various completion marks. These marks are earned by defeating specific bosses or completing certain challenges with that particular character. The placement of the mark on the post-it note corresponds to a specific boss or challenge. Successfully beating a boss for the first time with a character will grant you the corresponding completion mark.

The Post-it Note Layout

The post-it note is divided into several sections, each representing a different endgame boss or challenge:

• Mom’s Heart/It Lives: Located at the top-center of the post-it note.
• Isaac: Found on the top-left.
• ??? (Blue Baby): Located on the top-right.
• The Lamb: Positioned on the bottom-right.
• Mega Satan: Placed at the bottom-center.
• Hush: Located in the middle-left.
• Delirium: Found in the middle-right.
• Mother: Located at the bottom-left.
• The Beast: Located in the middle-bottom.

How to Obtain Each Completion Mark

Each completion mark requires you to defeat a specific boss in a standard run. Here’s how to achieve each one:

Mom’s Heart/It Lives

Defeating Mom’s Heart ten times unlocks It Lives, which then replaces Mom’s Heart. This completion mark is earned by defeating either Mom’s Heart (the first ten times) or It Lives afterwards. This is usually the first major milestone for new players.

Isaac

To obtain the Isaac completion mark, you need to defeat Isaac in the Cathedral. This requires obtaining the Polaroid item (guaranteed after defeating Mom’s Heart/It Lives enough times), allowing you to enter the Cathedral after defeating Mom. Beating Isaac unlocks items and other secrets associated with the character you used.

??? (Blue Baby)

Defeating ??? (Blue Baby) in the Chest grants you this completion mark. Similar to Isaac, you need to obtain the Polaroid item to enter the Chest after defeating Mom. This is a challenging fight and requires a strong build.

The Lamb

The Lamb completion mark is earned by defeating The Lamb in the Dark Room. Accessing the Dark Room requires obtaining the Negative Polaroid after defeating Mom, offering an alternative path to the Chest. The Lamb is a formidable foe, demanding careful planning and execution.

Mega Satan

Mega Satan’s completion mark is arguably the most complex to achieve. You must find either Dad’s Key, get lucky with a ‘Get out of Jail Free card’ or open the door using two Angel room key pieces. These key pieces drop from Angel Rooms, which have a low spawn rate unless you avoid Devil Deals. Mega Satan is a multi-stage boss, testing your endurance and damage output. Defeating Mega Satan with a character often unlocks powerful items.

Hush

To get the Hush completion mark, you need to defeat Hush in the Blue Womb. The Blue Womb is accessible by defeating Mom in under 30 minutes. Hush is a bullet-hell style boss with high health, requiring precise movement and sustained damage.

Delirium

The Delirium completion mark is obtained by defeating Delirium in the Void. The Void can be accessed through various means, such as using a Void portal that spawns after defeating Hush or other endgame bosses. Delirium is a chaotic boss that shapeshifts into other bosses, making each fight unpredictable and challenging.

Mother

The Mother completion mark is earned by defeating Mother in Corpse. This requires going through an alternative route that starts by bombing a special marked skull in the Depths II, acquiring the Knife Pieces and using them to open the door to Corpse. Mother is a tough boss with unique attack patterns.

The Beast

To get The Beast completion mark, you must defeat The Beast in the Home. This requires defeating Mother and then following a specific sequence of events that leads to the ascent and the final battle with The Beast. This is considered one of the most challenging and rewarding completion marks to obtain.

Tips for Achieving Completion Marks

• Prioritize Unlocks: Focus on unlocking key items and characters that make subsequent runs easier. Judas and Cain, for example, can be very powerful.
• Learn Boss Patterns: Understanding the attack patterns of each boss is crucial for survival. Practice makes perfect.
• Optimize Your Build: Synergies between items can significantly increase your damage output and survivability. Experiment with different combinations.
• Manage Resources: Conserve your health, bombs, keys, and pills wisely. Knowing when to use them can make or break a run.
• Embrace the Grind: The Binding of Isaac is a game of perseverance. Don’t get discouraged by failed runs. Learn from your mistakes and keep trying.

The Importance of Completion Marks

Beyond the personal satisfaction of conquering challenges, completion marks are integral to unlocking new content in The Binding of Isaac. Achieving specific completion marks with different characters unlocks new items, trinkets, starting items, and even new characters. These unlocks can significantly impact your future runs, providing new strategies and challenges. Completing all the completion marks on all characters is a monumental task, but it’s also the key to experiencing everything the game has to offer.

Furthermore, completion marks provide a clear visual representation of your progress. They serve as a roadmap, guiding you toward the game’s many secrets and challenges. For completionists, the pursuit of these marks is the driving force behind countless hours of gameplay.

The Binding of Isaac: Rebirth, Afterbirth, Afterbirth+, and Repentance

The game has seen several expansions, each adding new content, characters, and challenges. The most recent expansion, Repentance, significantly overhauled the game, adding new paths, bosses, and items. While the core mechanics of completion marks remain consistent across all versions, the specific challenges and unlocks may vary. Therefore, it’s essential to consult a guide specific to the version you are playing.

Strategies for Specific Completion Marks

Some completion marks are notoriously difficult to obtain. Here are some strategies for tackling these challenges:

Mega Satan Strategies

As mentioned earlier, accessing Mega Satan requires either Dad’s Key or two Angel Room key pieces. Focusing on Angel Rooms is often the best strategy. Avoid taking Devil Deals, as this drastically reduces the chance of Angel Rooms spawning. Items that increase your chance of finding Angel Rooms, such as the Rosary Bead or the Mitre, can be invaluable. Another strategy is to find the ‘Get out of Jail Free’ card, which will automatically open the door to Mega Satan.

Hush Strategies

Defeating Mom in under 30 minutes can be challenging, especially with weaker characters. Prioritize damage output and movement speed. Items like the Stopwatch or the Book of Revelations can be incredibly helpful. The Stopwatch slows down enemies, making it easier to dodge attacks, while the Book of Revelations guarantees Angel Room spawns, potentially leading to powerful items.

Delirium Strategies

Delirium’s unpredictable nature makes him one of the most difficult bosses in the game. Focus on building a versatile build that can handle various situations. Items that provide invincibility or temporary damage boosts, such as the Holy Mantle or the Chaos Card, can be game-changers. Be prepared for a long and chaotic fight.

Mother Strategies

The alternate path to Mother is long and treacherous, requiring you to find and combine the Knife Pieces. Be cautious of curse rooms and enemies that can inflict status effects. Focus on building a strong defense and consistent damage output. Items that provide flight or spectral tears can be particularly useful.

The Beast Strategies

The final ascent to The Beast is a gauntlet of challenging encounters. Conserve your resources and prioritize survival. Items that provide healing or temporary invincibility can be crucial. The final battle with The Beast is a multi-stage fight that requires careful positioning and precise timing.

Conclusion

The completion marks in The Binding of Isaac are more than just checkboxes; they represent a journey of skill, perseverance, and discovery. Each mark tells a story of overcoming challenges and mastering the game’s intricate mechanics. Whether you’re a newcomer just starting your adventure or a seasoned veteran striving for 100% completion, understanding these marks is essential for unlocking the full potential of The Binding of Isaac. So, dive in, embrace the chaos, and start earning those completion marks!

By understanding the significance of each completion mark and employing effective strategies, players can navigate the challenging world of The Binding of Isaac with greater confidence and achieve their goals. Remember to adapt your strategies based on the character you are playing and the items you acquire along the way. Happy hunting!

[See also: The Best Characters in The Binding of Isaac]

[See also: How to Unlock All Characters in The Binding of Isaac]