The ability of Rune-Tail's Essence applies only to damage that would be dealt to creatures its controller controls (C.R. 109.5).
Rune-Tail's Essence's ability doesn't change how trample works or otherwise change how combat damage is assigned (C.R. 510.1c-d apply generally and C.R. 702.19b applies to trample). Therefore, creatures assign combat damage the same way as though Rune-Tail's Essence's ability weren't active. For further details, see my comments 5 and 7 of this thread.
If your question is "can attacking creatures trample over blockers if all damage to the blockers will be prevented?" then yes. Damage assignment doesn't take into account any damage prevention effect, so a trampling attacker only has to assign as much damage as would be lethal to all its blockers and then can trample over the rest. Lethal damage is damage equal to the creature's toughness (assigned from this particular attacker and assigned from other attackers blocked by the same creature at the same time) or 1 damage from a source with deathtouch.
(Example for the multicreature block: If you attack with two 4/4s, ne with trample, and your opponent somehow blocks both with a 4/4, your 4/4 trampler can assign all its combat damage to the player, because the other 4/4 already assigns lethal damage to the blocker.)
Surrak has no other abilities or grants any other abilities that interact with damage. Trample is the only one.
Rune-Tail's Essence's ability doesn't change how trample works or otherwise change how combat damage is assigned (C.R. 510.1c-d apply generally and C.R. 702.19b applies to trample). Therefore, creatures assign combat damage the same way as though Rune-Tail's Essence's ability weren't active. For further details, see my comments 5 and 7 of this thread.
(Example for the multicreature block: If you attack with two 4/4s, ne with trample, and your opponent somehow blocks both with a 4/4, your 4/4 trampler can assign all its combat damage to the player, because the other 4/4 already assigns lethal damage to the blocker.)
Surrak has no other abilities or grants any other abilities that interact with damage. Trample is the only one.
Former Rules Advisor
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