Agent's Toolkit

Agent's Toolkit enters with a +1/+1 counter, a flying counter, a deathtouch counter, and a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Whenever a creature you control enters, you may move a counter from Agent's Toolkit onto that creature.
{2}, Sacrifice Agent's Toolkit: Draw a card.

Perrie, the Pulverizer

When Perrie enters, put a shield counter on target creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Whenever Perrie attacks, target creature you control gains trample and gets +X/+X until end of turn, where X is the number of different kinds of counters among permanents you control.

Twitching Doll

{T}: Add one mana of any color. Put a nest counter on Twitching Doll.
{T}, Sacrifice Twitching Doll: Create a 2/2 green Spider creature token with reach for each counter on Twitching Doll. Activate only as a sorcery.

Reluctant Role Model

Survival — At the beginning of your second main phase, if Reluctant Role Model is tapped, put a flying, lifelink, or +1/+1 counter on it.
Whenever Reluctant Role Model or another creature you control dies, if it had counters on it, put those counters on up to one target creature.

Crystalline Giant

At the beginning of combat on your turn, choose a kind of counter at random that Crystalline Giant doesn't have on it from among flying, first strike, deathtouch, hexproof, lifelink, menace, reach, trample, vigilance, and +1/+1. Put a counter of that kind on Crystalline Giant.