you can use pistons to push end crystals off obsidian

End Crystals can be pushed by pistons while placed on obsidian. This should not be possible, as End Crystals are intended to remain stationary

Steps

Place obsidian in the ground

Place a piston to the right of it on top of ground level

Place a end crystal on the obsidian

Place a lever on the backside of the piston and trigger it