The remainder of this article contains lore created collaboratively by the Blaseball community.
During an undefined point in history a frog became self aware. This frog then, through a series of widely debated mishaps, came into the possession of one Gerund Panthocide of the Tokyo Lift. It was from then on known as Frogslayer.
The biggest circulated story of Frogslayer is that they were received from Lotus Mango as a gift, and Gerund, while knowing nothing of frogs, couldn't say no to those eyes. They then strapped a knife to the frog and agreed to keep it as a pet. After several mishaps in which Frogslayer was pitched, batted, thrown in anger, dunked in breading and almost fried, and slept on, Gerund started to suspect that Frogslayer was no normal frog. They are pretty sure, however, that Frogslayer is NOT a god, but it's on thin ice.
No one knows quite how old Frogslayer is.
No one knows the origin of Frogslayer.
All anyone knows is that up until Yusef put a sheath on that knife Frogslayer was incredibly deadly to ankles.
As of the writing of this entry it is unknown if Frogslayer has managed to kill a God. According to Gerund, the answer is no, but the haunted look in Frogslayer's eyes implies otherwise.
Frogslayer is notably different from other blaseball adjacent frogs in that no known method of destruction has been found. Despite Gerund's accidental pitching of Frogslayer, and the subsequent batting of it, Frogslayer remained remarkably unharmed. Frogslayer was, in fact, delighted by the adventure and subsequent flight, despite the impact which would have killed a normal frog. Numerous events since which would have caused Frogslayer's untimely(?) demise have been just as ineffectual. Frogslayer is definitively immune to: crushing, boiling, impact/bludgeoning damage, piercing damage, being electrocuted, kicking, being thrown with force, horses, being incinerated, fall damage (all kinds), being skewered, and being breaded. The team refused to do further testing due to "not wanting to hurt the little guy."
Frogslayer seems to be, almost always, having a good time. Even when almost being fried Frogslayer's response was to simply eat some breadcrumbs and hop merrily away once rescued by team captain Stijin Strongbody from the impending doom of being boiled in hot oil. Stijin, despite the frog's nonchalance, cites it as "incredibly anxiety inducing," and stated, "Gerund needs to keep track of it if it is going to live with us. It's so small, someone could step on it! I'm just stressing out about it honestly..." Gerund's retort was, "It's an indestructable frog. It is always having a good time." And to shrug her shoulders.
Frogslayer's current gear loadout includes:
1). Small knife in sheath (sometimes out of sheath)
2). A little cloak with a symbol representing the Panthocide Clan.
3). A Positive Can-do Attitude.