Google Sheets 2 cells with identical functions, one is true, one is false; why?

Question

Normal Behavior

I am creating a spreadsheet to track character builds in D&D 5e. I am trying to have the cells below "Barbarian Unarmored Defense" and "Monk Unarmored Defense" check for values in the lower ranges, then return a blank if they are filled or levels in their corresponding class are not taken. The Monk one works fine with the formula designed, seen here;

The exact same formula in the next cell returns differently

Markdown Table

A1 Scores	B1 Strength	C1 Dexterity	D1 Constitution	E1 Intelligence	F1 Wisdom	G1 Charisma	H1	I1 Core	J1 Level	K1 Proficiency	L1 Per Rest Class Resources	M1	N1	O1	P1
A2 Base	8	10	10	10	16	10			10	4	Artificer Prepared Spells	Barbarian Rage	Rage Damage	Bardic Inspiration	Song of Rest
A3 Adjust									Spell Slots	Pact Slots		3	+2
A4 Mod Adjust											Blood Curses & Hemocraft Die	Cleric Prepared Spells	Channel Divinity<br>(Cleric/Paladin)	Druid Prepared Spells	Wild Shapes (Druid)
A5 Mod	-1	=IF((SIGN(ROUNDDOWN((C2-10+C3)/2+C4))<0), ROUNDDOWN((C2-10+C3)/2+C4), "+" & ROUNDDOWN((C2-10+C3)/2+C4))	+0	+0	=IF((SIGN(ROUNDDOWN((F2-10+F3)/2+F4))<0), ROUNDDOWN((F2-10+F3)/2+F4), "+" & ROUNDDOWN((F2-10+F3)/2+F4))	+0
A6 Save	-1	+0	+0	+0	+3	+0		Indomitable<br>(Fighter)	Sneak Attack<br>(Rogue)	Ki Points<br>(Monk)	Martial Arts Dice	Unarmored Movement (Monk)
A7 Proficient?										5	1d6	10ft
A8 Expert?								Paladin Prepared Spells	Favored Foe<br>(Ranger)	Nature's Veil<br>(Ranger)	Sorcery Points	Arcane Recovery
A9
A10 Stats	Current HP	Max HP	AC		Class Levels	Artificer	Barbarian	Arcane Trickster Levels	Eldritch Knight Levels		Eldritch Invocations	Mystic Arcanum 6th	Mystic Arcanum 7th	Mystic Arcanum 8th
A11 Base		0	13				5
A12 Adjust					Bard	Blood Hunter	Cleric	Barbarian Unarmored Defense	Monk Unarmored Defense
A13 Temp Effect								=IF(OR(ISBLANK($H$15), NOT(ISBLANK(I19:M19)), NOT(ISBLANK(J16:P16))), "", 10+$F$5+$C$5)	=IF(OR(ISBLANK($H$15), NOT(ISBLANK(I19:M19)), NOT(ISBLANK(J16:P16))), "", 10+$F$5+$C$5)	13	0	0
A14					Druid	Fighter	Monk	Mage Armor	Padded/Leather Armor	Studded Leather Armor	Hide Armor	Chain Shirt	Scale Mail / Spiked Armor	Breastplate
A15 Level	Rolled HP	Level					5
A16 1	Always Max		11		Paladin	Ranger	Rogue
A17 2			12					Ring Mail	Chain Mail	Splint	Plate	Shield	Custom	Custom
A183			13		Sorcerer	Warlock	Wizard		Requires 13 STR	Requires 15 STR	Requires 15 STR
A19 4			14
A20 5			15
A216			16		Subclass Select
A22 7			17		Artificer	Barbarian	Bard	Blood Hunter	Cleric	Druid	Fighter	Monk	Paladin	Ranger
A23 8			18
A24 9			19
A25 10			20
A26

Troubleshooting & Spreadsheet Link

The exact same formula works in the cell next to it, with all the same cell addresses and everything... so I expected them to output the same value. Steps I have taken to troubleshoot, reverting each after attempt;

• Changes to the ranges or cell IDs at all continues to return an empty cell If I change the true condition--that is always output, regardless of whether the other cells are filled or blank

• Changes to the false condition are never output, regardless of whether the other cells are filled or blank

• Emptying or filling H15 does not affect the output of I13's function

Answer 1

You need to array-enable your current formula as such:

=arrayformula(IF(OR(ISBLANK($H$15), NOT(ISBLANK(I19:M19)), NOT(ISBLANK(J16:P16))), "", 10+$F$5+$C$5))

• the reason being a simple NOT(ISBLANK(J16:P16)) does not automatically apply to the whole range of J16:P16; if you are applying this formula in Column J(any possible row) it picks only J16 as the target cell. if applied in Column_L then target cell is L16 and so on...
• Since Barbarian Unarmored Defenseis outside the zone (as highlighted in the screenshot) it evalutes to TRUE and the output results to blank

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