At a certain point in Pokemon Soul-Silver/Heat-Gold, the legendary beasts start wandering about the game map and it is possible to encounter and battle them. Naturally, I want to catch them all, but they are really tough customers and I have to drastically whittle their HP if I aim to succeed.
The thing is, there is always the risk of accidentally depleting their HP, causing them to faint. Will this effect me adversely in some way, or will they simply respawn at some later time with restored HP (I am worried seeing how their HP remains consistent through all encounters with them, meaning they sustain the damage I've dealt them each time I've battled them and then had them flee)?
I would rather you don't give any "plot" spoilers in your answer, if at all possible.