Slippery Bogbonder

Flash
Hexproof
When this creature enters, put a hexproof counter on target creature. Then move any number of counters from among creatures you control onto that creature.

Skullbriar, the Walking Grave

Haste
Whenever Skullbriar deals combat damage to a player, put a +1/+1 counter on it.
Counters remain on Skullbriar as it moves to any zone other than a player's hand or library.

Titanoth Rex

Trample
Cycling {1}{G} ({1}{G}, Discard this card: Draw a card.)
When you cycle this card, put a trample counter on target creature you control.

Gift of the Viper

Put a +1/+1 counter, a reach counter, and a deathtouch counter on target creature. Untap it.

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.