Combo of the day:
Horobi, Death’s Wail ($0.46) & Asceticism ($7.12)
The punchline is, asceticism lets you regenerate your opponent’s creatures! For some reason.
So your creatures won’t ever suffer Horobi’s effect (without you wanting them to,) while you can deliver poison-packed “salvation” to your opponent for the low low cost of 1G.
While we’re on horobi, let’s mention another unintended consequence of card wording:
Funnily enough, the cost of vish kal’s final ability doesn’t require he actually have counters. Removing 0 counters to give a creature -0/-0 is a valid activation. So, without resources, you can machine-gun creatures forever. Don’t want to run horobi? Just like blue? A funny thing about both of these combos is that you can utilize them with three other cards: