I am currently homebrewing a set of "brawler" races, modeled after the nonhumanoid characters in Brawl Stars. For one race, I've made a homebrew cantrip, Cactus Grenade. Is it balanced?

Cactus Grenade

Conjuration Cantrip.

Casting Time: 1 Action,

Range: 60 feet

Components: S M(a small cactus)

Duration: Instantaneous

You throw a small cactus at a target within range. Make a ranged spell attack against the target. On a hit, the target takes 1d4 piercing damage. Whether you hit or not, the cactus explodes and anyone within 5 feet of the target (including the target itself) must succeed in a Dexterity saving throw or take 1d4 piercing damage. The spell's damage (both on impact and area) increases as you reach higher levels. 2d4 at 5th level, 3d4 at 11th level, and 4d4 at 17th level.

One spell you could compare it to another cantrip that does AOE damage: Thunderclap (Elemental Evil Player's Companion, pg. 168):

Range 5 ft

You create a burst of thunderous sound that can be heard up to 100 feet away. Each creature within range, other than you, must succeed on a Constitution saving throw or take 1d6 thunder damage.

The spell’s damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).

How does your spell compare:

Pro:

• Long range (60 feet, vs focused on yourself)


• Also has the chance to deal 1d4 damage to one target on hit


• Does not have the penalty that the blast can be heard from 100 ft away

Con:

• Less damage (d4 die, vs d6)

Neutral:

• Dex save, vs Con save


• Requires material component


• Piercing damage and thunder damage are both extremely unlikely to be resisted. While many creatures have resistance to "Bludgeoning, Piercing, and Slashing from Nonmagical Attacks", this is a magical attack so it would bypass this resistance.

The cantrips Sword Burst (SCAG p. 143) and Word of Radiance (XGTE 171) are nearly identical. They keep the d6 damage die and the 5 ft range centered on yourself, but switch the save (DEX and CON respectively) and the damage type (radiant and force respectively). This appears to be the standard for a balanced AOE cantrip.

Your spell is significantly better: the reduction in damage from the smaller damage die (which only reduces average damage per target by 1) will generally be outweighed by the chance to damage the primary target twice, while the long range makes this much safer to use (to make good use of damage from Thunderclap, you need to be surrounded by enemies).

It's not hugely overpowered on its own (unless a clever player comes up with synergies that I'm not thinking of now) and if it's a racial feature, it may be alright so long as the race is balanced by being weaker in other ways.

If you want to make it more balanced with other cantrips, I would do some the following:

• lower the range (the 20 ft range for a thrown flask of Holy Water seems like a good figure)


• remove the primary target damage and attack roll (this also has the benefit of reducing the complexity of the cantrip)

Even with those changes, though, it's still going to be more slightly powerful than Thunderclap unless you add an extra downside (maybe the cactus can be caught and thrown back?)

Unbalanced, it's more like a 1st level spell

Comparison against ice knife

The first level spell ice knife has very similar mechanic, but with higher damage dice. Both have a 60' range, but ice knife delivers 1d10 initial damage on a hit, and then 2d6 cold on a failed dex save (hit or miss) that effects both the targets and those around.

As your cantrip increases in power with level all damage goes up. With ice knife, only the cold damage increases. As you level up, your cantrip will become more powerful than the spell requiring a resource.

Add language for the cactus creation

Right now, the wording implies that you need a cactus (even though there is no material component.) You should update the copy for it to include something like:

You create a small cactus...

Unknown

Because this cantrip is only allowed for an unknown race it would be impossible to judge it on its own.

Example

1. Race X


2. Movement 5ft


3. Blind in direct Sunlight (no dark vision)


4. Vulnerable to Sunlight, Fire, Necrotic


5. Cannot Mount or Ride other creatures

Cactus thrower as a cantrip you can throw a cactus for 4D20

The above example would be an unplayable race in most campaigns with an epic level cantrip.
I am not suggesting the Race X is balanced. By having a unique cantrip tied to an unknown race makes both impossible to judge.