
When Bolg enters, you may sacrifice another creature. When you do, Bolg deals damage equal to that creature's power to another target creature. If excess damage was dealt this way, amassamassPut X +1/+1 counters on an Army you control. It's also a Goblin. If you don't control an Army, create a 0/0 black Goblin Army creature token first. Goblins X, where X is that excess damage. (Put X +1/+1 counters on an Army you control. It's also a Goblin. If you don't control an Army, create a 0/0 black Goblin Army creature token first.)
Hover an underlined rule to see what it means.
Read from the rules text. A card that enables a keyword makes or is the thing; a card that rewards it gets better when you have it. Two cards interact when one enables what the other rewards.