Soul Immolation

Once you've announced that you're casting a spell or activating an ability, players can't take actions until you've finished doing so. Notably, opponents can't try to destroy or otherwise remove your creatures to stop you from blighting as part of paying the cost of that spell or ability.

The creature you choose to put -1/-1 counters on doesn't have to have enough toughness to survive the process. For example, if you blight 2, you can choose to put the counters on a 1/1 creature you control.

If a creature has +1/+1 counters and -1/-1 counters on it, state-based actions remove the same number of each so that it has only one kind of those counters on it. For example, if a creature has three +1/+1 counters on it and two -1/-1 counters are put on it, state-based actions will remove two of each of those kinds of counters, leaving the creature with just one +1/+1 counter.