Use the maximum HP possible from the dice instead of the average given (eg. 6d12 = 72 instead of 39), or at least a higher portion of the maximum quantity
Increase AC
Give it extra damage of a different type
Give non-lair monsters lair actions, and give monsters with lair actions an even stronger lair action they can use when below half-health.
Same with legendary actions
Look at older DnD editions and see if the monster or any similar monsters have extra abilities you can add
Edit: I should have specified that these are in ascending levels of difficulty for the DM, but are also more interesting
The risk in 1 & 2 is that monsters become a slog and characters are no longer heroes. If you need to hit a monster 30 times before it dies (because half misses due to AC, and you need a lot of hits due to HP), it’s just slow and boring.
Lair actions and distractions/barricades to get to BBEG are where its at. There’s a trap in the way. New support keeps popping in until something is destroyed. Something changes drastically halfway through the fight.
Use the maximum HP possible from the dice instead of the average given (eg. 6d12 = 72 instead of 39), or at least a higher portion of the maximum quantity
Increase AC
Give it extra damage of a different type
Give non-lair monsters lair actions, and give monsters with lair actions an even stronger lair action they can use when below half-health. Same with legendary actions
Look at older DnD editions and see if the monster or any similar monsters have extra abilities you can add
Edit: I should have specified that these are in ascending levels of difficulty for the DM, but are also more interesting
The risk in 1 & 2 is that monsters become a slog and characters are no longer heroes. If you need to hit a monster 30 times before it dies (because half misses due to AC, and you need a lot of hits due to HP), it’s just slow and boring.
Lair actions and distractions/barricades to get to BBEG are where its at. There’s a trap in the way. New support keeps popping in until something is destroyed. Something changes drastically halfway through the fight.