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Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.

Proficiency Bonus

As you are increasing the CR of the creature its proficiency bonus will also increase. For a creature between CR5 and CR9 this will be a +3.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong editionPathfinder, since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.

Proficiency Bonus

As you are increasing the CR of the creature its proficiency bonus will also increase. For a creature between CR5 and CR9 this will be a +3.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.

Proficiency Bonus

As you are increasing the CR of the creature its proficiency bonus will also increase. For a creature between CR5 and CR9 this will be a +3.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from Pathfinder, since there are no official rules for 5e, but I find they translate fairly well with a little work.

3 added 46 characters in body
source | link

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

I would increase proficiency bonus to the +3 or even +4 to be the equivalent to an npc character of a similar level.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.

Proficiency Bonus

As you are increasing the CR of the creature its proficiency bonus will also increase. For a creature between CR5 and CR9 this will be a +3.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

I would increase proficiency bonus to the +3 or even +4 to be the equivalent to an npc character of a similar level.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.

Proficiency Bonus

As you are increasing the CR of the creature its proficiency bonus will also increase. For a creature between CR5 and CR9 this will be a +3.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

2 added 75 characters in body
source | link

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

I would increase proficiency bonus to the +3 or even +4 to be the equivalent to an npc character of a similar level.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

I would increase proficiency bonus to the +3 or even +4 to be the equivalent to an npc character of a similar level.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities reskined as a full orc. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

Add Class Levels

Unfortunately 5e does not have set rules on this unlike previous editions. However my favourite way to beef up a monster manual enemy is to add class levels.

3 levels of Fighter (Champion) would grant Great Weapon Fighting Style, Second Wind, Action Surge and Improved critical. Barbarian would also suit but flavour to your preference.

I would increase proficiency bonus to the +3 or even +4 to be the equivalent to an npc character of a similar level.

Give magic items

As you suggested some higher level magic items would definitely help. A +1 weapon would close the gap on what I see as the war chiefs biggest weakness against a Paladin. Low attack bonus will struggle to hit the paladin regularly. Assuming he has an AC of 20 or above as most lvl 8 paladins would.

Improve Base Stats

You could choose to increase the War Chiefs base stats. A strength of 20 or even higher would make him feel like an epic enemy.

Give Feats

Add a feat or two to increase his combat ability without modifying the base class. Great Weapon Master would be a great choice.


Alternatively

Don't use the War Chief and just make a npc based on half-orc racial abilities (Player's Handbook) reskined as a full orc or the Orc racial traits from Volo's Guide to Monsters. This is my normal approach for BBEG or significant enemies. I find class levels allow you to multiclass to get exactly the feel for the class you want. Barbarian 2/Fighter 6 would feel like an angry orc war chief to me.


Monster Advancement Rules: these are from the wrong edition since there are no official rules for 5e, but I find they translate fairly well with a little work.

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