Every budding trainer ever to set foot in the world of Pokémon has had to contend with a tough, sometimes heartbreaking decision before jubilantly screaming "I choose you" at their Nintendo handheld of choice. This is a perfectly normal thing to do, but actually weighing up which of each Pokémon generation's three main starter Pokémon is the best can be a tricky prospect.

Ever since the great Squirtle vs Charmander debate of the late 90s (sorry, Bulbasaur), players have argued over which main companion reigns supreme (it was Squirtle) in every new set of Pokémon games.

Be it their type, moveset, evolution chain or their overall design, the love a trainer has for their starter 'mon becomes an unbreakable bond, and choosing a partner often requires careful consideration.

With Pokémon Sun and Moon now out in the wild (it's released on 23 November for UK Poké-fans), Rowlet, Litten and Popplio are all ready and waiting to join you on an adventure – but which should you pick?

Below IBTimes UK runs the Grass-Fire-Water trio and ranks them from best to worst based on how they stack up against Pokémon Sun and Moon's early Island Trials – the series' equivalent of Pokémon Gyms – as well as some Nature and hidden stat tips for those interested in competitive online battles.

This isn't favouritism, honestly. Some Pokémon are just genetically superior.

Pokemon Sun and Moon Rowlet evolutions
(L-R) Rowlet, Dartrix and Decidueye The Pokémon Company

Rowlet – Best

Type: Grass/Flying

Evolves into: Dartrix (Level 17), Decidueye (Level 34)

Best Natures: Adamant, Lonely, Gentle

We love Rowlet. It's a cheerful-looking, mildly rotund owl that wears a bowtie. How could you not love it?

Putting his weapons-grade levels of adorable aside, however, Rowlet still sits at the top of Sun and Moon's starter triangle when pitted against the Trial challenges thanks to his Grass/Flying typing and early move-set.

Aside from a pesky fourth Trial that pits you against Kiawe's Fire-type beasties, the first three are a breeze with Rowlet in tow, as its combination of Flying (Peck at Level 8) and Grass (Leafage from the start and Razor Leaf at Level 15) physical attacks would wreak havoc on the Normal, Fighting and Water Trials with which you begin your adventure.

Things get tougher later on against Rock, Ghost and Dark-themed Trials once Decidueye gains the Ghost dual-typing in place of Flying, but its large movepool, useful resistances and impressive special defence help matters. The only other downside is the Rowlet chain's middling Speed stat.

For the competitive battlers out there, high Attack or Defense Effort Values (EVs) and Individual Values (IVs) work out well in the long run. Sacrifice the (already low) Special Defense or Special Attack stats if you are after the best nature.

Pokemon Sun and Moon starter evolutions
(L-R) Popplio, Brionne and Primarina The Pokémon Company

Popplio – Average

Type: Water

Evolves into Brionne (Level 17), Primarina (Level 34)

Best Natures: Modest, Calm, Quiet, Sassy

Popplio is officially the 'Marmite' starter Pokémon of the seventh generation, with fans split on whether the pirouetting sea lion is the cutest thing ever or a garish abomination.

As a fighting choice, Popplio firmly occupies the middle ground when it comes to Sun and Moon's early Trials. Its single Fairy-type move Disarming Voice (Level 8) gives Melemele's Kahuna – the Fighting-type obsessed Hala – a firm kicking, but it unfortunately has to wait until its final stage evolution to actually earn Fairy as a secondary type.

When the mid-game Rock and Fire Trials arrive, the Popplio family comes into its own, but you may want to pick up Flying (Pikpek becomes a monster) and Electric (you can find Pichu very early on) Pokémon to help out.

End-game battlers need to be aware of Primarina's painfully low Speed and fragile HP/Defense – avoid physical attackers with Grass, Electric, Poison and Steel moves. Thankfully, it has mammoth Special Attack and Defense stats. We suggest optimising these stats with EVs/IVs/Nature and taking a little hit on the already low Speed.

Pokemon Sun and Moon Litten evolutions
(L-R) Litten, Torracat and Incineroar The Pokémon Company

Litten – Worst

Type: Fire

Evolves into Torracat (Level 17), Incineroar (Level 34)

Best Natures: Brave, Adamant

It hurts me to say this, but the wish-I-could-hug-it Fire pussycat Litten is by far the weakest of the Alolan three.

Don't expect to see any cries of "It's super-effective!" until you are up against the Grass-type Trial's Totem Laurantis and prepare to weep against the super-powered Wishiwashi on the second island.

Torracat learns the Dark move Bite at level 24, but Litten's kitty chain is restricted to weak Normal and Fire attacks and very few decent Technical Machine (TM) moves until late-game.

Things don't improve with its final form, Incineroar. The wrestler-styled moggy gains a solid spread of resistances thanks to its secondary Dark type, but its stats are spread so broadly that it fails to excel at anything. It even has similar Speed stats to Primarina, but without the huge boost elsewhere.

Its high HP and decent Defense and Special Defense stats mean Incineroar can take a bit of a beating, but its returning strikes are a tad underpowered. Drop the Special Attack or Speed with its Nature and try to push its base Attack stat higher with IVs/EVs.

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