You can ride striders on top of other mobs (such as zombies and baby zombies, etc) making you completely immune to them. The strider will literally treat the baby zombie like its a block and will jump and start walking on top of it. With a 1 block high wall, you can do the same with any 2 high mob. Just make sure they are all melee mobs. Alternatively, just block their line of sight (e.g. put a block inside a ghast and you can walk over it with a strider).