I'll report an RSE bug.
Today i used Leech seed on a Blissey with Ludicolo, (Ludicolo was at 20%). Blissey used thunderbolt and deal 19% damage, then ludicolo died buffed by the sandstorm, before leech seed's effect can be activated. Then, I sent out Marowak and the effect of leech seed, at the end of turn does not activated. This is a bug, Leech seed effect must be activated after a kill, all status condiction effect must be activated at the end of the turn, such as: burn, leech seed, toxic, WISH and so on, unlike the new gen metagame. I'm not sure if burn work after a kill, but maybe in the next days i will report it. I don't have the log 'cause i closed the battle, but i don't have problem to post another one.