Nyahaha Boats are DIRT CHEAP, I could just give you one, they're friggin cheap. You can also kill monsters out at see. Voys have spells they can use at sea. But I shall tell you the chart of weakness.
Win -Loose
Crusaders-Rangers (Rangers have low defence and dont have a way to counter stealth so 1 IS will kill them)
Tank-Crusader (Crusaders have barly any strength and they have no way of killing a tank, its next to impossible, They hit like 4, and tanks heal easy.)
Voy-Tank (Voys have a set damage regardless of defence, so no matter what they will hit alot)
SealMaster-Voy (Seal Masters can stop the Voy from using spells so the seal will win)
Rangers-SM (Rangers have a good base attack so even without spells the Ranger can win)
SM-Crus (Sm has a spell called True Sight wich will allow them and their team to see stealthed Crus's and attack)
Cleric-Crus (Clerics also have Truesight)
Crus-Voy (A crusader could stun and then IS a voy, unless the voy catches the crus)
Now you can MvM (Multiple vs. Multiple) and I found the ideal team. 1 Cleric 1 Voy 2 Crusaders and if theres one, take a ranger.
Cleric can truesight to get cruses and use Energy Shield to tank. Voy can do mass amounts of damage, and some voys have alot of HP aswell. 2 Crusaders for stunning, stealthing and slashing.
Rangers for getting the ones that run ^_^