That's 4.
Forest
School of Piranha, returning the Herd to my hand
Cast the Herd again
Done
Modus Pwnens: 14
Hand: 19
Play:
(U) Mountain
(T) Plains
(T) Island
(T) Swamp
(T, T) Forest
Onslaught (Whenever you play a creature spell, tap target creature)
(U) Standing Troops (1/4, Vigilance)
(T) Dauthi Jackal (2/1, Shadow. BB, Sacrifice Dauthi Jackal: Destroy target blocking creature)
(S) Crashing Boars (4/4, Whenever Crashing Boars attacks, defending player chooses an untapped creature he or she controls. That creature blocks Crashing Boars this turn if able.)
GY: Allay, Nausea
RFG:
Spiderman: 16
Hand: 8
Play:
(T) Mt
(T) Plains
(T) Swamp
(T,T) Forest x2
(T) Island
Predatory Hunger (Whenever Modus plays a creature spell, put a +1/+1 ctr on enchanted creature)
(U) Standing Troops (3/6, Vigilance) *Hungry* (2 counter)
(S) Jackalope Herd (4/5, When I play a spell, return ~ to its owner's hand)
(S) School of Piranha (3/3, At the beginning of my upkeep, sac ~ unless I pay 1U)
GY: Maniacal Rage, Raging Goblin, Dauthi Jackal
RFG: