Space Invader is a premium 5 star card introduced as the top reward for the Primal Rifts event.
Space invader has Sweeping Blow, Nobility 7 and Lifesap 7.
Sweeping Blow and Lifesap is a good combo. Nobility 7 converts 35% of damage sustained into attack. Unfortunately Space Invader has no defence against lockdown, and he might just die with a lot of unused attack.
The skillset is similar to Phantom Liege, a commonly available card from the coupon altar and guild maps. Phantom Liege has 'Seals' in place of Space Invader's 'Nobility 7' and one level higher Lifesap.
The 'Seals' ability of Phantom liege goes great in tandem with the Sweeping blow/lifesap combo.
The rarity of Space Invader makes it difficult to meld. It is easier to meld a Phantom Liege with immunity and protect him against lockdown, hence activating lifesap every turn and improving survivability.
Surprisingly another premium card 'Lava Wyrm' also has the same sweeping blow+lifesap combo, with a mediocre third skill.
Have you seen Space Invader in action yet? What do you think?