Well those are abilities that are also combat helpful for a combat oriented assassin, but an assassin with all support abilities can be effective too. I mean look at the hero ability combos I posted not their individual abilities.
As in if those were the only 8 skills that demigod had:
(heal that does damage and later through a different skill upgraded to a chain heal that does damage, faster respawn with less effects w/ shorter time magic reduction buff (two seperate skills into one cast?), slow aura for demi's (and with an upgrade creeps), 3 second invulnerability ultimate like ability for evreything near by, take more damage debuff, slowing attack passive)
That would be a support assassin in my book. I mean he dosn't even have to hit hard, they'll be so slow, taking extra damage, and have troubles killing anything, let alone if they do they're back faster. Wheather solo or team, he'd do better with a team, but he can do plenty fine in 1v1.
I mean jeeze, high damage assassins? who needs em ( 
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