Summary
There’s not much a little prayer can’t help you with. One of the most powerful classes inDungeons & Dragonsis the Cleric, and they also have one of the most unique class features: Divine Intervention. You ask your Deity for help, roll a percentile dice — a d100 — and, depending on the roll, your Deity will assist you with whatever trouble you are having.
The thing is, you can technically ask for anything, but at the same time, you can’t. It falls to the Dungeon Master to decide how much your Deity will actually do. So whether you’re a Cleric or a DM preparing yourself for the party’s Cleric, we have some ideas for you.

Bonus: Consider The God And The DM
As we mentioned, you can technically ask for anything, making this feature almost a Wish spell at first. But, as the feature itself says, the DM will choose how the intervention will work, and your domain and the particular God you follow are things to consider, too. Asking such a benevolent Deity like Illmater to do a killing spree for you will likely not work, but a warmonger God, like Bane, could say yes to that.
And, as stated, the DM makes the final decision. This means that, though you can ask for something specific, as we’ll show, a vague sentence can do wonders here. If your intervention works during a boss fight, simply asking for help but not describing the type of help you want has a higher chance of working.

8Punish Or Vanquish Your Foes
From A High-Level Free Spell To Just A Bunch Of Damage Dice Rolling
If you’re playing a DPS Cleric, like a War or Tempest Domain, this is a fitting way to use your intervention. Ask your Deity to kill all enemies near you is a pretty standard way to deal with a fight, or at least hurt them severely, by free-casting a high-level spell likeMeteor Swarmthat only affects enemies (though how the damage will go is for your DM to decide).
Alternatively, punishing a powerful enemy could be a temporary debuff for the fight, such as making them susceptible to a condition they are usually immune against or making them vulnerable to a fitting damage type.

7Save Yourself From An Incoming TPK
Your God To The Rescue
If everything is going south, and you no longer see a way out of the situation, praying is fitting. And since saving your party from a Total Party Kill (TPK) can be done in many ways, your DM has all the freedom they need to save you in a way that fits your Deity. Technically, killing all enemies near you is a way to save you from a TPK.
But gentler Gods can do this by teleporting you away from danger, for example, or even teleporting enemies away from you. This is essentially the Hail Mary of D&D, and it can prevent campaigns from ending too soon.

6A Free Rest
Who Even Sleeps Eight Hours A Day?
You don’t need to use Divine Intervention only when fighting. If your characters are in a hurry but can’t stop to rest for plot reasons, you could ask your Deity to recover your party’s abilities, instantly giving you the effects of a long rest, for instance.
Still, you could also do this in a fight to fully recover yourself and your friends to their full power so you can waste it all against your Boss. This effect could also remove possibleExhaustion points,or negative effects such as curses — though Remove Curse is an option here, too.

5Free Resurrections
Free Of Charge
Resurrection spells are often expensive. What about doing this without any cost? Or better yet, you could ask for multiple resurrections during a fight if things are that sour on the battlefield.
And despite how powerful multiple resurrections are, it’s not a big thing to ask most Deities anyway, and it fits your class. Most DMs would probably be okay with asking a God to bring someone back.

4Divine Gear
Gods Can Forge Legendary Weapons, Right?
The most problematic thing about this idea is that your DM will need time to consider what equipment would be appropriate for you and your Deity. So, let them know you intend to use it this way, see if they’re okay with it, and try it once per long rest until you succeed.
It can be apowerful magic weapon,armor, or multiple less powerful items you can combine on yourself or share with your party. It’s an excellent way to convert them to your God, too.

3You’re Stuck
Divine Guidance Is Always Helpful
The game stopped because you and your party didn’t pick up on the clues going on. Now, everyone is going in circles around the city and has no idea what the next step would be. Or you have many places you’re considering visiting, but you’re afraid of which one is the best call.
Though a simple prayer and ability check could be enough for your DM, a Deity could give you more information than you would normally know or help you see what is happening with the plot through a direct conversation.

2Temporary (Or Permanent) Power-Ups
Permanent Could Be Too Much, Though
Wouldn’t it be helpful if your entire party could fly right now? Sure, the power-up itself shouldn’t be your decision, but asking for a temporary power boost or an extra skill that fits your Deity and could be very useful during the current fight is a great idea.
It also lacks the anti-climatic issue of having your God end a major battle, as they’ll boost you and your friends and make the fight a bit more balanced while still letting you win the fight yourself.

1Ask Your God To Help NPCs
Divide And Conquer
Sometimes, we have to make hard choices. You need to choose which place you’ll go or who you’ll save, fully knowing that you’re leaving people in danger for doing so. For example, the city is about to be attacked. Should you stay and protect the King, or should you go and protect the innocent commoners?
Divine Intervention is a cheesy way to get both, though. Whoever you choose to save, you can ask your Deity to look out for the others, ensuring they’ll be in capable, divine hands. Your prayers don’t need to be for your benefit only.