The best way I've found to tame them is to use a basilosaurus,then lure a single electro away from the group and have it shock you (on the mount). Wait about a second for the shock to end and quickly jump off and spam E (keep biotoxin in the 0 slot). *A large school of these can quickly stun and immbobilze larger mounts and knockout players fairly quickly, so use caution!*

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