Making An Arena Fight With A Hydra Memorable (5E)
I’m running D&D 5e for my players. I am planning a big arena fight with a Hydra while they’re in the big city for some downtime. (It’s part of a big end-of-year adventurers showcase that I’m pretty excited for them to play in!)
Struggling with ideas for how to make it a memorable fight (and tough enough) to take on 5 PCs at lvl 9.
Would you be willing to lend some expertise?
Thanks for the question, Jack!
RPT GM, I’m going to provide my tips in 5E lingo. But even if you don’t play D&D fifth edition, you hopefully find the advice portable to your game system.
Solo = Doomed
In D&D 5E, the Action Economy favours the characters.
Already the party outnumbers the creature. Even with the hydra’s multiple heads, it’s a single opponent that creates instant focus fire from every character.
Add in the extra actions the party gets each round from 5E rules, and solo creatures of almost any level are doomed against a group of 9th level PCs.
Sponge Up Character Actions
I think your first order of business would be to even up the sides a bit.
Add more foes.
You could throw in minions to distract PCs and use up their actions. Every attack not made against the hydra extends the creature’s life. And with luck, a minion or three could hit and bruise the party.
If you don’t object to tweaking monsters, you could have each severed head spawn a new hydra during the combat. That would make for a cool special effect, as well.
A third option: make it a triangle fight by adding rivals. Is there a faction who would love to compete against the PCs in the arena match for the most glory?
Another big weakness solo creatures have is maneuvering.
Even if foe speed exceeds the fastest PC’s, spells and smart flanking ensure the party always threatens the creature.
To even these bad odds we use terrain.
If we drop difficult terrain in the arena, deep mud for example, then the creature’s move suffers too. But where’s the creature going to go? An arena offers no escape.
However, all the characters could be affected by the terrain, making the party less agile overall. A small win for poor hydra.
If desired, you could swing things further in the monster’s favour by choosing Hazards that hinder the monster less than the party.
For example, a hydra has a Swim 30 feet Move. Make the fight in water and the battle becomes interesting….
A hydra can also hold its breath for 1 hour. No one said the swimming pool cover had to be off during the fight, right? How long can the characters hold their breath? Minutes in 5E. So it’s not a lethal threat, but I bet your players will still freak out to have the characters trapped under water the entire battle.
Last, note how the hydra has a ten foot reach with its attacks?
Foe reach has an inverse relationship with combat space. Meaning, the longer the foe’s reach, the tighter you want the PCs around it. If characters cannot escape reach as often, the foe gains a small edge because it has more attack choices.
For example, an injured PC often withdraws to heal or get healing. But if the PC cannot escape the enemy’s reach, the combat becomes a white knuckled match unless characters sacrifice Actions to top up their health.
In 5E you have two cool mechanics to make monsters more powerful.
First is Legendary Actions. I’m about to add a lesson to my Wizard of Combat course on this very topic, actually.
A monster with this enhancement gets, in general, 3-5 additional Actions each round of combat.
Action Economy restored.
It also means the creature can effectively act between character turns. So look for synergies there.
A hydra out of the box has no Legendary Actions. You could customize the creature with some, however.
Find ways to challenge certain characters with custom Legendary Actions without nerfing the PCs.
For example, you might create a breath weapon where the creature can inhale a lot of water and push it back out again, buffeting victims and causing damage. Extra damage will get more players on the edge of their seats.
The second 5E mechanic you might want to look at is Lair Actions.
These function the same as Legendary Actions. Rectify an imbalanced Action Economy, lay more damage onto the party, and make the creature harder to kill with Lair Actions.
If you do this, here’s a neat option.
Give the party a Lair Action too.
You could say the hydra is a veteran in the arena. It feels like home turf, so it’s considered a lair. Add those Lair Actions.
But you could also say the party are arena veterans or experts in some other way such that they get a Lair Action of your design too.
Here’s how we do that.
Pick a PC who doesn’t get involved much in combat. Take one of their weakest attacks or an interesting Action and turn that into a Lair Action named after the character.
Let the player wield their party’s Lair Action as something else to help them engage.
Trigger an event to happen every round to make combat even more chaotic…and interesting for the PCs.
Maybe make an events table like this:
1d6 Arena Events
- Spectators enter the arena. Could be a streaker. Could be a hapless fan. Could be a planned crowd surprise. Turns out, though, the spectators are seasoned veterans and no easy foes, and they choose to side with the hydra.
- Collapse. A section of the arena collapses. The hydra tries to escape, stomping on citizens while others get crushed under debris and the panicked crowd.
- Thumbs down. A key NPC is the guest of honour. They are displeased with the fight, though, and turn their thumb down. This results in releasing more monsters into the arena.
- Fire. Flames erupt and threaten to engulf the entire stadium.
- New Hazard. At the top of next round, handlers deploy a new Hazard. Caltrops, different weapons, potions — something that complicates the fight and benefits the hydra.
- Interference. A spectator throws something dangerous at a PC.
From a fiction point of view, perhaps the city loves its pet hydra. When the crowd sees the PCs winning, they get upset and interfere.
Let’s focus purely on the memorable factor for a moment.
One great option: up the Stakes.
Roleplay to goad characters into making side bets. Now PCs have extra skin in the game.
However, do not make side bets that merely depend on win or loss.
Instead, make bets about who does the most damage, who gets the kill shot, or who has the best style as voted by the crowd.
Set up small competitions like this to add flavour and dimension to your match.
Another great option: Dilemma.
Hook character goals and backgrounds into the event. Perhaps a Hapless Spectator has a relationship with a PC. Or minions relate to an ongoing Mission. Or a character who fears something must confront that thing during the fight.
Another option: tiered victories. Offer PCs different rewards depending on how well or fast the party wins. If the party wins in three rounds, they get full rewards. Each round more it takes, the rewards diminish.
Missions vs. Death
Last idea for you. This will combo memorableness with difficulty.
Don’t make the match be a fight to the death. At least for the party.
Instead, stipulate some additional challenge or requirement for victory.
For example, handlers have painted big white circles on the creature’s body. Belly, tail, three heads, and chest.
PCs must pierce each circle at least once to win. For called shots like these, you might make such attacks Disadvantage or give the creature an AC bonus.
Maybe a really different Mission would work for your group. Perhaps the PCs must subdue the creature and then make it feel bad for being a jerk (a hydra has no languages but it does have a decent Wisdom and a functional Charisma score).
Or the PCs have to teach the enraged creature a trick and make it perform the trick for the crowd.
Supplying a Mission instead of a death verdict might work quite well for your group.
So there’s a few ideas for you.
To increase the Challenge Rating of the match, make the encounter more difficult with terrain or minions, or give the creature additional abilities via Legendary Actions and maybe Lair Actions.
To make the arena battle memorable, consider adding events and fiddling with Stakes and Dilemmas.
I hope this helps!