A combo of Cultivate and Explosive Vegetation is awesome, and the more colors in your deck or format (like Five Color), the better this is
This effect is mostly found on blue cards
This one requires two mana and only prevents combat damage, but it justifies its existence with a ferocious effect
Aristocrat decks that make and sacrifice numerous creature tokens, for example, are perfect for Mirkwood Bats
There are some truly degenerate things you can do with this thing in the command zone
Ondu Spiritdancer - With this one out first, you get two copies of Yojimbo Champions from Beyond This enchantment gives you tokens, card draw, and a giant team-wide buff