Pokemon described in this note is the third of the “famous Squirtle”, belonging to the named trainer and appearing in more episodes. Squirtle trained by Tierro stands out (apart from his dancing personality, consistent with the trainer) in that he was the only one that evolve into the final form, Blastoise (Ash’s Squirtle never evolved, May’s Squirtle, as far as we know, evolved only to Wartortle). He is also distinguished by the fact that, unlike the two mentioned above, he did not appear in any films. However, like Ash’s Squirtle, this one also is raised in the company of other Kanto starters (although Ash was the trainer of all, and in this case, Tierro is friends with the two other trainers, with Bulbasaur and Charmander).
Below is a list of the episodes in which this Pokemon appears – the first number is the “overall” episode number, the second is the episode number within the sub-series, in this case, XY. Episode numbers according to the Bulbapedia.
838 – XY039 – Summer of Discovery! – Squirtle’s debut.
839 – XY040 – Day Three Blockbusters!
840 – XY041 – Foggy Pokémon Orienteering!
841 – XY042 – Battling into the Hall of Fame!
843 – XY044 – Showdown at the Shalour Gym! – Flashback.
864 – XY065 – Good Friends, Great Training! – Wartortle’s debut.
885 – XY086 – A Legendary Photo Op! – Flashback
889 – XY090 – Tag Team Battle Inspiration! – Blastoise debut.
925 – XY126 – Valuable Experience for All!
931 – XY132 – A Towering Takeover! – Minimal part.
934 – XY135 – Rocking Kalos Defenses! – Minimal part.
935 – XY136 – Forming a More Perfect Union! – Minimal part.