I tried this card a few times and it feels absolutely bonkers. Necrobinder has an insane amount of big attacks that pair well with it. Thing is that at cost 1 even just upping a few normal attacks and unleash is decent, especially as it works the same turn you play it.
They also stack so getting +150% or +225% is doable. I can imagine that higher ascensions will be less forgiving towards high cost attacks so pairing with osty is probably a good idea for defense.