2014-04-26 : If one or more, but not all, of the targets of the first ability are illegal when that ability tries to resolve, no counters will be placed on illegal targets. You can't change the distribution you announced when you activated the ability; the excess counters are just lost.

2014-04-26 : You announce how many counters will be placed on each target creature as you activate Ajani's first ability. Each target must receive at least one counter.