The best pet for grinding in Mine a Planet depends on which planet you are farming and which stat you want to optimize, but for most situations the Astral Cat is the top pick because it grants both Drill Speed and Rare Drop bonuses. This guide covers the optimal pet for each planet, the best pet combinations for specific grinding routes, and the recommended loadout for end-game players pushing the highest material income per hour.
For the broader pet tier list and stats, see our Mine a Planet pet tier list. For the pet hatching strategy, see our Mine a Planet pet egg hatching guide. This principle applies broadly across all progression stages and is one of the most reliable optimization levers in the game.
Best Pet by Planet
The optimal pet for each planet depends on the planet's primary material and the crafting milestone you are pushing toward. The exact mechanics vary slightly by patch, but the underlying principle remains consistent across all player playstyles.
| Planet | Best Pet | Reason |
|---|---|---|
| Earth | Dust Bunny | Auto pickup for fast Common ore cycles |
| Mars | Iron Pup | Drill Speed + Damage bonus |
| Europa | Moon Fox | Rare Drop +15% on Europa |
| Volcano | Volcano Phoenix | Smelt Speed for Mythril Bar pipeline |
| Nebula | Astral Cat | Drill Speed + Rare Drop for Stardust |
| Void | Cosmic Wolf | Drill Speed + XP for Void Shards |
The Earth pet recommendation is the Dust Bunny because of its auto pickup, which is the most useful early-game bonus. The other planets favor pets with high Drill Speed and Rare Drop bonuses because those bonuses compound with every swing.
Best Pet Loadout for End-Game Players
For end-game players pushing the highest material income per hour, the optimal pet loadout is Astral Cat (slot 1), Cosmic Wolf (slot 2), Volcano Phoenix (slot 3), and Iron Pup (slot 4). This loadout stacks four different pet bonuses for maximum effect across multiple stats.
| Slot | Pet | Primary Bonus | Secondary Bonus |
|---|---|---|---|
| 1 | Astral Cat | Drill Speed +15% | Rare Drop +12% |
| 2 | Cosmic Wolf | Drill Speed +18% | XP Bonus +10% |
| 3 | Volcano Phoenix | Smelt Speed +25% | Ore Multiplier +10% |
| 4 | Iron Pup | Drill Speed +8% | Damage +5% |
The combined Drill Speed bonus from this loadout is +41%, which compounds with the Prestige Shop Drill Speed multiplier and the reforge Drill Speed stat. The combined Rare Drop bonus is +12%, which compounds with the Prestige Shop and the reforge.
Why Pet Switching Matters for Maximum Grinding
Switching pets as you move between planets is a small optimization that adds up over time. Equipping the Moon Fox on Europa adds +15% Rare Drop, but unequipping it on Volcano would lose the Volcano Phoenix's +25% Smelt Speed. The pet you equip should match the planet you are actively grinding.
The optimal pet switching strategy is to dedicate one pet slot to a planet-specific specialist and the other three slots to general-purpose all-arounders like the Astral Cat and Cosmic Wolf. This way, you can swap specialists as you move between planets without losing the all-around bonuses.
Best Pet Combos for Specific Routes
Some grinding routes benefit from specific pet combos that are not covered by the general loadout above. Here are the recommended pet combos for the most popular grinding routes. Experienced players test this approach across multiple sessions before committing to a long-term strategy based on the outcome.
| Route | Pet Combo | Reason |
|---|---|---|
| Stardust farming on Nebula | Astral Cat + Cosmic Wolf + Moon Fox | Stack Drill Speed and Rare Drop |
| Mythril farming on Volcano | Volcano Phoenix + Astral Cat | Smelt Speed + Drill Speed |
| Drill Piece burst on Earth | Dust Bunny + Astral Cat | Auto pickup + Drill Speed |
| Void Shard farming on Void | Cosmic Wolf + Astral Cat | Drill Speed + XP |
How Pets Stack With Other Bonuses
Pet bonuses stack additively with each other and multiplicatively with the Prestige Shop and reforge bonuses. A player with maxed Prestige Shop Drill Speed upgrades and a perfect Drill Speed reforge can see total Drill Speed bonuses of roughly 100%+ (which means swinging roughly twice as fast as baseline).
The compounding effect is significant — a player with maxed everything will swing roughly 2-3x faster than a player with no bonuses, which translates directly into 2-3x more material income per hour. This is why pet selection is one of the most impactful end-game optimizations.
Pet Slot Composition for Maximum Grind
The pet slot composition that maximizes your grind output depends on whether you are focusing on raw ore throughput or rare drop accumulation. For raw ore throughput, the optimal trio is a +Drill Speed pet plus a +Ore Multiplier pet plus a +Smelt Speed pet, which stacks three complementary bonuses. For rare drop accumulation, the optimal trio is a +Rare Drop Chance pet plus a +Drill Speed pet plus a +Damage pet, which maximizes both your drop rate and your node-break rate.
For a fully optimized pet slot, the combo bonuses matter as much as the individual stats. Pets that grant a bonus to all three of your drills simultaneously are extremely valuable, and they should be prioritized over single-stat pets even if the raw stat numbers look smaller. For more on pet combo math, see our pet combo strategy guide.
Reforge Synergy With Active Pets
The bonus from your active pet stacks with the bonus from your active drill's reforge, which means a perfectly rolled Ore Multiplier reforge combined with a +Ore Multiplier pet can yield roughly 2x the base Ore Multiplier of an unrolled drill with no pet. This synergy is what makes the late-game grind feel so much faster than the early-game grind, and it is also why pet optimization and reforge optimization should always be tackled together rather than sequentially.
For players who are just starting their pet optimization journey, focus first on unlocking the Epic pet slots (which grant the third pet slot), then on hatching rare-tier pets, and only then on optimizing the pet stats themselves. This sequence ensures you have the slot count and the pet base power before you invest Drill Pieces into pet upgrades.
Frequently Asked Questions
What is the best pet for Stardust farming on Nebula?
The Astral Cat is the best pet for Stardust farming because it grants Drill Speed and Rare Drop bonuses that both compound on every swing. The Cosmic Wolf is a close second. Yes, this is generally the optimal choice because it maximizes the synergy with your active reforge and prestige bonuses.
Should I switch pets when I move between planets?
Yes, switching pets to match the planet is a small optimization that adds up over time. Equip the Moon Fox on Europa, the Volcano Phoenix on Volcano, and the Astral Cat on Nebula. Generally yes, but the optimal timing depends on your current resource reserves and your active biome's node HP profile.
Can I have two of the same pet?
Yes, you can carry duplicates. Some players carry two Astral Cats with different passive spreads to test the optimal stat combination. Yes, but the optimal approach depends on your current progression stage and your stockpile of supporting materials. Combining this insight with active pet bonuses and prestige multipliers yields compounding benefits that accelerate overall progression.
What is the best pet for new players?
The Dust Bunny is the best starter pet because its auto pickup is the most useful early-game bonus. Save the Astral Cat and Cosmic Wolf for end-game progression. Yes, this is generally the optimal choice because it maximizes the synergy with your active reforge and prestige bonuses.
Do pet bonuses apply to trade income?
No, pet bonuses apply only to in-game material drops and Drill Piece income. They do not affect the trade market value of materials, which is determined by player supply and demand. Always verify the trade against the current market rate before confirming, because traders bundle low-value items to mask cost.
How Pet Bonuses Compare to Reforge Bonuses
Pet bonuses and reforge bonuses are both important for end-game grinding, but they affect different stats. Pet bonuses typically boost Drill Speed, Rare Drop, Smelt Speed, XP, and Damage, while reforge bonuses can boost Damage, Ore Multiplier, Drill Speed, Rare Drop Chance, and Smelt Speed.
The overlap between pet bonuses and reforge bonuses is in Drill Speed and Rare Drop Chance. For these stats, both pet and reforge bonuses stack, which means a player with a maxed Drill Speed pet and a maxed Drill Speed reforge can see total Drill Speed bonuses of roughly 100%+.
For stats that are only available through pets (like XP Bonus and Smelt Speed), pet bonuses are the only source. For stats that are only available through reforges (like Ore Multiplier), reforges are the only source. Players who want to maximize all stats need both a strong pet loadout and a strong reforge build.
How Pet Bonuses Compare to Drill Tier Bonuses
Pet bonuses and drill tier bonuses are different types of multipliers that affect different aspects of grinding. Drill tier affects base damage and base ore multiplier, while pet bonuses affect Drill Speed, Rare Drop, Smelt Speed, and other stats that compound with every swing or batch.
A high drill tier (Astral Annihilator) gives you high base damage and high base ore multiplier, but it does not directly affect your Drill Speed. A high Drill Speed pet (Astral Cat) gives you faster swings, which means more swings per hour, which compounds with the drill tier bonuses. The two systems work together, not against each other.
For end-game players, the optimal strategy is to maximize both drill tier and pet bonuses. A maxed Astral Annihilator with a maxed Astral Cat pet loadout is roughly 2-3x more efficient than a maxed Astral Annihilator with no pet bonuses.
Why Pet Grinding Builds Are Slightly Different From Pet PvP Builds
While the game is not heavily focused on PvP, the Underground Arena does include some combat encounters where your pet bonuses affect your damage output. For PvP-focused Arena play, the optimal pet loadout shifts slightly to favor pets with Damage Bonus over pets with Smelt Speed.
For pure Drill Piece grinding, the Smelt Speed pet is valuable because it speeds up your batch times. For Arena play, the Damage pet is more valuable because it boosts your combat damage output. Players who split time between grinding and Arena should consider keeping two pet loadouts — one for grinding and one for Arena.
Pet Switching on Long Sessions vs Short Sessions
For long grinding sessions (2+ hours), the pet switching overhead is a small percentage of the total session time, so optimizing for each planet makes sense. For short sessions (15-30 minutes), the pet switching overhead is more significant, and it is often better to stick with a single loadout rather than switching pets multiple times.
The optimal session strategy depends on your typical play pattern. If you are a long-session player, switch pets freely. If you are a short-session player, stick with a versatile all-around loadout. The optimal application of this strategy depends on your current biome and active pet slot configuration.
Pet Stacking Limits and Why They Exist
There is a soft cap on the total pet bonus effect you can stack, which is roughly +150% to any single stat. Beyond that, additional pet bonuses yield diminishing returns because the underlying calculation has diminishing returns built in. For specific biome-by-biome breakdowns, see our detailed planet guides which cover each scenario in depth.
For most players, the soft cap is not a concern because the maximum pet bonuses from a maxed pet loadout rarely exceed the soft cap. The cap matters only for players who stack maxed pet bonuses with maxed Prestige Shop bonuses and maxed reforge bonuses on the same stat.
When to Replace a Pet
Pets should be replaced when a higher-tier pet becomes available and offers a strictly better bonus spread. For example, replace the Iron Pup (Drill Speed +8%) with the Astral Cat (Drill Speed +15%) as soon as you can acquire an Astral Cat. The 7% Drill Speed increase is meaningful for end-game grinding.
The replacement timing depends on your hatch rate and trade market availability. Most players replace their Iron Pup with an Astral Cat within the first week of reaching Nebula. Veteran players typically learn to recognize these patterns within the first 10-15 hours of focused play.