Why isn't this a draw?

With only one light squared bishop, and no pawns, against the lone bishop, if I try to block all escape squares for my king I will still have the option to block the check, as one of the pieces I use to block one of the escape squares for my king one of the pieces blocking my escape square would necessarily be a rook or queen that can block the check. I would need another light square bishop or a pawn in order to be able to block all my kings escape squares without being able to block the check.

I coded a bug. I tested many things, but not this position.

Sigh, it's even worse than I imagined. White (the horde) can mate with same-square-colored bishops if either:
* Black has two bishops on the opposite square color (or can underpromote to make it so, which may require capturing a bishop)
* Black has a bishop on the opposite square color and can get checkmated en route to promotion, for example with Pa2 and Bb1; or with Pc2 and the king surrounded by Black pieces

Watch me fumble over this at travis-ci.org/ddugovic/scalachess :-)

Oh joy, past me provides an answer:
> In horde chess, the horde cannot win on * V K or [BN]{2} v K or just one piece since they lack a king for checkmate support.
> Technically there are some positions where stalemate is unavoidable which this method does not detect; however, such are trivial to premove.
github.com/ornicar/scalachess/commit/0b61734aabcd0027e17ce84e894d476c6b0dbbc4#diff-e52977847e5eb5f6fb1085329e2144e0R69-R72

Sorry, but I see "End of the time"... Usually it matters... but I'm not perfect sure to have undestand this situation.

Edit: I've understand. I think that chess are a rappresentation of ancient battles, and in them only if Kings can't gives any order the kingdom is disgregates. So, if a knight, that isn't a king, is the only fighter in the battle, make no similitudines force as a tie.