Bone pit

{t}:Add {c} to your mana pool
{t}:Put a bone counter on Bone pit and create a 0/1 skeleton token, activate this ability only if you control no 0/1 skeletons
{t}:Create a 3/3 skeleton beast token, activate this ability only if bone pit has 3 or more bone counters on it and you control no 3/3 skeleton beast
{t} Pay one life:create a 6/6 skeleton dragon token with flying, activate this ability only if bone pit has 6 or more bone counters on it and you control no 6/6 skeleton dragons