What makes grease a good spell?

Question

I often see people list grease as good go-to 1st level spell. Why is this?

The spell description lists 3 of its uses: forcing saves and slows movement of enemies, disarming enemies, and preventing grabs. To me these seem pretty situational.

My group often does not contain a wizard and when it does he never casts grease, so I have not witnessed or experienced it in live combat.

Is there some other use of the spell that I am forgetting or not aware of? Does the fact that it has 3 situational uses make more than just a situational spell?

Answer 1

Grease is a phenomenal spell for its spell slot, especially once you get a few Caster Levels under your belt so that it lasts. For many, grease is the go-to 1st-level combat spell after the first few levels.¹

There are a number of reasons for this.

Area Effect

Grease has a goodly-sized area, that simultaneously isn’t so large that it’s impossible to avoid your allies with it.

SR: No

This eliminates one of the more annoying defenses a Wizard may have to worry about, especially later. This means that grease remains good long after you have higher-level spell slots available, unlike color spray and sleep.

Conjuration

Conjuration is widely regarded as the best arcane spell school in the game. It’s got the most or second-most spells of any school² – and an enormous number of them are very powerful. It’s also fantastically flexible, with a very broad range of effects available to it (battlefield control, like grease, teleportation, summoning and calling effects, even great blasting spells like orb of force from Spell Compendium). This makes it a very good school to specialize in – either literally, as a Conjurer, or simply through feats, prestige classes, and the like. And if you do, grease can benefit from this specialization.

Double-threat

When grease is cast under you, you have to pass your Reflex save to avoid falling in the first place, and then you have to pass your Balance check to move (and in the process once again risk falling!). For such a low-level spell, that’s rather reliable. There are a lot of monsters with pitiful Balance checks out there.

Reliability in the Face of Defenses

Grease hurts your enemies even if they pass both save and check. They can only move at half speed, and more importantly, the Balance skill has this rule:

You are considered flat-footed while balancing, since you can’t move to avoid a blow, and thus you lose your Dexterity bonus to AC (if any). If you have 5 or more ranks in Balance, you aren’t considered flat-footed while balancing. If you take damage while balancing, you must make another Balance check against the same DC to remain standing.

Two things here. One, every attack forces a Balance check versus falling down. Even the Wizard can sit there and hit enemies with ray of frost to force those checks. A ranged touch attack against a flat-footed opponent is very easy – against a lot of foes, it’s AC 10. A Wizard 4 with Dex 14 has a 70% chance of hitting that. A Wizard’s allies can have even better chances, and get more attacks.

Dungeons & Dragons 3.5 Version

And then there’s the fact that Sneak Attack applies against enemies that are flat-footed. That means, no matter how well you do on your Balance check, if you don’t have 5 ranks, you are now very, very scared of the Rogue. You’ve taken a penalty to AC, he’s going to attack you twice, and he’s getting +2d6 or more bonus damage on both attacks. For a 3rd to 4th level character, that is very dangerous. So dangerous that I consider 5 ranks of Balance a high priority for just about every character.

And then you have to make a check against falling down. Twice.

Pathfinder Version

In Pathfinder, only creatures who move through grease are flat-footed. How this works is unclear: the strictest interpretation I can find is that they are flat-footed only for Attacks of Opportunity made during their motion. I cannot find a solid answer on whether a creature who moves through grease is still flat-footed once they stopped (e.g. on other creatures’ turns).

That said, teamwork can take advantage of this. If one player casts grease, another uses bull rush or other effects to move enemies through it, and the Rogue takes Attacks of Opportunity, this can rack up some nice “free” damage. If they remain flat-footed after this motion, the Rogue can really go to town, since Pathfinder does not have the rule about 5 ranks in Balance protecting you the way 3.5 does.

And having a creature stay stock-still in the middle of grease to avoid these penalties is still a great form of area denial.

Conclusion

Grease hits an area with a very reliable form of suck. There are a lot of creatures and characters that are going to be seriously inconvenienced by grease even if they never fall down.

Which means that enemies are going to try to get out of it, and stay out of it. Welcome to area-denial: you can now tell your enemies where they can, and can’t, go. Battlefield control is one of the most powerful tactics in 3.5, and grease is very, very good at it for its level.

Footnotes

¹ Before you start hitting their HD caps, color spray and sleep are usually preferred over grease, and after a while the fact that grease is on the ground makes it much less useful because so many things are flying – at that point, though, you’ll be hard-pressed to find many good combat uses for any 1st-level spell.

² Which school has the most spells depends on books in play; for example, there are more Transmutations in the Player’s Handbook than Conjurations. Not coincidentally, for those who don’t think Conjuration is the best school, Transmutation is usually the school that’s taking that title.

Answer 2

Strategic Area Denial

Grease is a way to deny an area to an enemy. The area is remarkably large and, at low levels, the denial is sufficient that it will alter the enemy's tactics. Therefore, by casting this in a corridor, the wizard can shape the nature of a fight, or, if the enemy chooses to ignore the spell, grant a significant edge to her team.

It's one of the favourite spells because it's one of the best "save-or-suck" spells of early level, comparable only to sleep or colour spray.

Answer 3

I have heard tale of great adventurers that would coast down long hallways of flame in a boat, casting down foes by sword, bow and fire!

No, seriously, "back in the day" I knew two players that once, possibly twice, used a one-two combo employing Grease. Some of this may have been GM liberties granted the players, so no "you can't do that" because I sat at a table where this was done in T1-4. However, that said, I think it's fair to "rules lawyer" this use of Grease.

The wizard would cast Grease on the hall and someone would produce fire (a torch or flint). The hall would alight in flame (grease is flammable in most common uses or expectations), often to capture goblins and other beasties enmasse. Then a boat (I recall a flat bottom row boat) was pulled from a Large Bag of Holding, the party jumped in the boat, and pushed their way down the greased hallway.

This apparently was a common trick (some say to have become something of a gaming "urban" legend). Something similar was recounted on the podcast Fear the Boot in context of another gaming group (in that anecdote I recall a force spell of some kind being employed to propel the party in the boat).

And yet, I experienced this actually taking place. I remember being somewhat aghast at the liberties bestowed by the GM as I didn't think it should work (how did the boat get forced in the Bag of Holding, etc). I did not protest then, if only because we were having a good time and a lot of laughter was had. I don't think I would protest today either, though I would want the PCs to have their ducks in a row in employing the combo.

This had to be after high school, so 1987-88. AD&D (1e).

Answer 4

A simple answer is that Grease is a rare spell that has many different uses. You can use it for battlefield control (effectively even at higher levels). You can use it for a ranged combat maneuver (disarm) which is again useful even into higher levels. And you can use it to help yourself OR allies avoid one of the most damaging maneuvers - being grappled. Either in advance or as a boost to Escape Artist checks while grappled (easier to cast on an ally but as a 1st level spell it isn't all that hard to make the concentration check to cast it on yourself while grappled)

This means that Grease is a spell that has a lot of utility - making it great for spontaneous casters with limited spell lists (i.e. Sorcerers in Pathfinder) and making it a good option for prepared spellcasters since it has so many uses it will likely come up at least once on most adventuring days.

In Pathfinder in particular there aren't a lot of spells that have so many different utilities - being both useful in combat as well as defensively.

Answer 5

You get TONS of use out of grease. It can be especially useful in conjunction with other effects. For example, if one character has the ability to create pits, well placed grease combined with pits is quite excellent. If you have a foe that loves to use charges, well-placed grease is excellent at stopping them. Defending a fortified structure and you have forces trying to scale the walls? Grease is an excellent way to slow them down. It's one of many first level "utility spells" that can be a gift that keeps on giving.

Answer 6

It's mainly good if you have front-liners who have reach or ranged attacks.

For clarification this answer only concerns the Pathfinder version of the spell and relevant rules on Acrobatics checks. Though the question is tagged for both DnD 3.5 and Pathfinder, DnD 3.5 may work very differently.

If you have a non-reach melee-combatant and is constantly wailing on an adjacent foe then putting grease under that foe won't really help. The foe will stay exactly where he is and keep attacking back and unless they actually move there aren't any relevant checks except the first check.

Despite its low level it usually becomes more valuable at higher levels where large-size strength based creatures begin appearing these creatures often have low dex, low reflex saves and often zero ranks in Acrobatics while they often have high immunity to direct attack spells due to high Will saves and or spell resistance. So Grease becomes disproportionately good.

What's really good is to use reach, especially if reach can be stacked with something like Enlarge Person, they cannot 5ft step which means it must spend a move action where they provoke and also cannot full-attack.

If you have a rogue with a ranged attack, they can ready it to hit as soon as they try to move and will get a sneak attack as they are flat footed, or position themselves where they can hit them as they stand up or try to move parallel.

Also as a Spell Level 1st you can put them in cheap spell storing items like Cracked Purple Ioun Stones which can store a single spell level and cast at will. As they are not affected by caster level they are good to stockpile as cheap CL1 scrolls. Which means these spells can just be put out quicker.

As to the specific wording of where Grease applies (pathfinder edition):

A grease spell covers a solid surface with a layer of slippery grease.

This means it literally a solid surface, as opposed to a liquid or a gas or a plasma (like fire). It is a spell of grease rather than a pot of mundane grease so may make solid things slippery that might otherwise be impossible to make slippery due to how absorbent or abrasive they are.

Do not assume a GM will consider the grease from this spell to be flammable, it is generally considered bad practice to surprise your overworked GM with such an idea in the middle of combat. Ask him or her well before combat or even before the session and discuss it fairly and reasonably (as in use reasons), consider what this means both ways in terms of verisimilitude and balance, how they might like being subject to the idea of grease being flammable.

Also, if it is flammable, agree how the damage should be modelled, how long it burns, how easy to ignite and so on. But something like that is bordering on homebrew. Nothing about this spell actually says it is flammable so don't presume it can be used that way.